eth: request id dispatcher and direct req/reply APIs (#23576)

* eth: request ID based message dispatcher

* eth: fix dispatcher cancellation, rework fetchers idleness tracker

* eth/downloader: drop peers who refuse to serve advertised chains

cmd/utils/flags.go

@@ -215,7 +215,7 @@ var (
 	defaultSyncMode = ethconfig.Defaults.SyncMode
 	SyncModeFlag    = TextMarshalerFlag{
 		Name:  "syncmode",
-		Usage: `Blockchain sync mode ("fast", "full", "snap" or "light")`,
+		Usage: `Blockchain sync mode ("snap", "full" or "light")`,
 		Value: &defaultSyncMode,
 	}
 	GCModeFlag = cli.StringFlag{

core/blockchain.go

@@ -629,9 +629,9 @@ func (bc *BlockChain) setHeadBeyondRoot(head uint64, root common.Hash, repair bo
 	return rootNumber, bc.loadLastState()
 }
 
-// FastSyncCommitHead sets the current head block to the one defined by the hash
+// SnapSyncCommitHead sets the current head block to the one defined by the hash
 // irrelevant what the chain contents were prior.
-func (bc *BlockChain) FastSyncCommitHead(hash common.Hash) error {
+func (bc *BlockChain) SnapSyncCommitHead(hash common.Hash) error {
 	// Make sure that both the block as well at its state trie exists
 	block := bc.GetBlockByHash(hash)
 	if block == nil {
@@ -736,30 +736,24 @@ func (bc *BlockChain) ExportN(w io.Writer, first uint64, last uint64) error {
 //
 // Note, this function assumes that the `mu` mutex is held!
 func (bc *BlockChain) writeHeadBlock(block *types.Block) {
-	// If the block is on a side chain or an unknown one, force other heads onto it too
-	updateHeads := rawdb.ReadCanonicalHash(bc.db, block.NumberU64()) != block.Hash()
-
 	// Add the block to the canonical chain number scheme and mark as the head
 	batch := bc.db.NewBatch()
+	rawdb.WriteHeadHeaderHash(batch, block.Hash())
+	rawdb.WriteHeadFastBlockHash(batch, block.Hash())
 	rawdb.WriteCanonicalHash(batch, block.Hash(), block.NumberU64())
 	rawdb.WriteTxLookupEntriesByBlock(batch, block)
 	rawdb.WriteHeadBlockHash(batch, block.Hash())
 
-	// If the block is better than our head or is on a different chain, force update heads
-	if updateHeads {
-		rawdb.WriteHeadHeaderHash(batch, block.Hash())
-		rawdb.WriteHeadFastBlockHash(batch, block.Hash())
-	}
 	// Flush the whole batch into the disk, exit the node if failed
 	if err := batch.Write(); err != nil {
 		log.Crit("Failed to update chain indexes and markers", "err", err)
 	}
 	// Update all in-memory chain markers in the last step
-	if updateHeads {
 	bc.hc.SetCurrentHeader(block.Header())
+
 	bc.currentFastBlock.Store(block)
 	headFastBlockGauge.Update(int64(block.NumberU64()))
-	}
+
 	bc.currentBlock.Store(block)
 	headBlockGauge.Update(int64(block.NumberU64()))
 }

core/blockchain_repair_test.go

@@ -79,10 +79,10 @@ func testShortRepair(t *testing.T, snapshots bool) {
 // already committed, after which the process crashed. In this case we expect the full
 // chain to be rolled back to the committed block, but the chain data itself left in
 // the database for replaying.
-func TestShortFastSyncedRepair(t *testing.T)              { testShortFastSyncedRepair(t, false) }
+func TestShortSnapSyncedRepair(t *testing.T)              { testShortSnapSyncedRepair(t, false) }
-func TestShortFastSyncedRepairWithSnapshots(t *testing.T) { testShortFastSyncedRepair(t, true) }
+func TestShortSnapSyncedRepairWithSnapshots(t *testing.T) { testShortSnapSyncedRepair(t, true) }
 
-func testShortFastSyncedRepair(t *testing.T, snapshots bool) {
+func testShortSnapSyncedRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//
@@ -119,10 +119,10 @@ func testShortFastSyncedRepair(t *testing.T, snapshots bool) {
 // not yet committed, but the process crashed. In this case we expect the chain to
 // detect that it was fast syncing and not delete anything, since we can just pick
 // up directly where we left off.
-func TestShortFastSyncingRepair(t *testing.T)              { testShortFastSyncingRepair(t, false) }
+func TestShortSnapSyncingRepair(t *testing.T)              { testShortSnapSyncingRepair(t, false) }
-func TestShortFastSyncingRepairWithSnapshots(t *testing.T) { testShortFastSyncingRepair(t, true) }
+func TestShortSnapSyncingRepairWithSnapshots(t *testing.T) { testShortSnapSyncingRepair(t, true) }
 
-func testShortFastSyncingRepair(t *testing.T, snapshots bool) {
+func testShortSnapSyncingRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//
@@ -203,14 +203,14 @@ func testShortOldForkedRepair(t *testing.T, snapshots bool) {
 // crashed. In this test scenario the side chain is below the committed block. In
 // this case we expect the canonical chain to be rolled back to the committed block,
 // but the chain data itself left in the database for replaying.
-func TestShortOldForkedFastSyncedRepair(t *testing.T) {
+func TestShortOldForkedSnapSyncedRepair(t *testing.T) {
-	testShortOldForkedFastSyncedRepair(t, false)
+	testShortOldForkedSnapSyncedRepair(t, false)
 }
-func TestShortOldForkedFastSyncedRepairWithSnapshots(t *testing.T) {
+func TestShortOldForkedSnapSyncedRepairWithSnapshots(t *testing.T) {
-	testShortOldForkedFastSyncedRepair(t, true)
+	testShortOldForkedSnapSyncedRepair(t, true)
 }
 
-func testShortOldForkedFastSyncedRepair(t *testing.T, snapshots bool) {
+func testShortOldForkedSnapSyncedRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3
@@ -250,14 +250,14 @@ func testShortOldForkedFastSyncedRepair(t *testing.T, snapshots bool) {
 // test scenario the side chain is below the committed block. In this case we expect
 // the chain to detect that it was fast syncing and not delete anything, since we
 // can just pick up directly where we left off.
-func TestShortOldForkedFastSyncingRepair(t *testing.T) {
+func TestShortOldForkedSnapSyncingRepair(t *testing.T) {
-	testShortOldForkedFastSyncingRepair(t, false)
+	testShortOldForkedSnapSyncingRepair(t, false)
 }
-func TestShortOldForkedFastSyncingRepairWithSnapshots(t *testing.T) {
+func TestShortOldForkedSnapSyncingRepairWithSnapshots(t *testing.T) {
-	testShortOldForkedFastSyncingRepair(t, true)
+	testShortOldForkedSnapSyncingRepair(t, true)
 }
 
-func testShortOldForkedFastSyncingRepair(t *testing.T, snapshots bool) {
+func testShortOldForkedSnapSyncingRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3
@@ -340,14 +340,14 @@ func testShortNewlyForkedRepair(t *testing.T, snapshots bool) {
 // crashed. In this test scenario the side chain reaches above the committed block.
 // In this case we expect the canonical chain to be rolled back to the committed
 // block, but the chain data itself left in the database for replaying.
-func TestShortNewlyForkedFastSyncedRepair(t *testing.T) {
+func TestShortNewlyForkedSnapSyncedRepair(t *testing.T) {
-	testShortNewlyForkedFastSyncedRepair(t, false)
+	testShortNewlyForkedSnapSyncedRepair(t, false)
 }
-func TestShortNewlyForkedFastSyncedRepairWithSnapshots(t *testing.T) {
+func TestShortNewlyForkedSnapSyncedRepairWithSnapshots(t *testing.T) {
-	testShortNewlyForkedFastSyncedRepair(t, true)
+	testShortNewlyForkedSnapSyncedRepair(t, true)
 }
 
-func testShortNewlyForkedFastSyncedRepair(t *testing.T, snapshots bool) {
+func testShortNewlyForkedSnapSyncedRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6
@@ -387,14 +387,14 @@ func testShortNewlyForkedFastSyncedRepair(t *testing.T, snapshots bool) {
 // this test scenario the side chain reaches above the committed block. In this
 // case we expect the chain to detect that it was fast syncing and not delete
 // anything, since we can just pick up directly where we left off.
-func TestShortNewlyForkedFastSyncingRepair(t *testing.T) {
+func TestShortNewlyForkedSnapSyncingRepair(t *testing.T) {
-	testShortNewlyForkedFastSyncingRepair(t, false)
+	testShortNewlyForkedSnapSyncingRepair(t, false)
 }
-func TestShortNewlyForkedFastSyncingRepairWithSnapshots(t *testing.T) {
+func TestShortNewlyForkedSnapSyncingRepairWithSnapshots(t *testing.T) {
-	testShortNewlyForkedFastSyncingRepair(t, true)
+	testShortNewlyForkedSnapSyncingRepair(t, true)
 }
 
-func testShortNewlyForkedFastSyncingRepair(t *testing.T, snapshots bool) {
+func testShortNewlyForkedSnapSyncingRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6
@@ -475,14 +475,14 @@ func testShortReorgedRepair(t *testing.T, snapshots bool) {
 // the fast sync pivot point was already committed to disk and then the process
 // crashed. In this case we expect the canonical chain to be rolled back to the
 // committed block, but the chain data itself left in the database for replaying.
-func TestShortReorgedFastSyncedRepair(t *testing.T) {
+func TestShortReorgedSnapSyncedRepair(t *testing.T) {
-	testShortReorgedFastSyncedRepair(t, false)
+	testShortReorgedSnapSyncedRepair(t, false)
 }
-func TestShortReorgedFastSyncedRepairWithSnapshots(t *testing.T) {
+func TestShortReorgedSnapSyncedRepairWithSnapshots(t *testing.T) {
-	testShortReorgedFastSyncedRepair(t, true)
+	testShortReorgedSnapSyncedRepair(t, true)
 }
 
-func testShortReorgedFastSyncedRepair(t *testing.T, snapshots bool) {
+func testShortReorgedSnapSyncedRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10
@@ -521,14 +521,14 @@ func testShortReorgedFastSyncedRepair(t *testing.T, snapshots bool) {
 // the fast sync pivot point was not yet committed, but the process crashed. In
 // this case we expect the chain to detect that it was fast syncing and not delete
 // anything, since we can just pick up directly where we left off.
-func TestShortReorgedFastSyncingRepair(t *testing.T) {
+func TestShortReorgedSnapSyncingRepair(t *testing.T) {
-	testShortReorgedFastSyncingRepair(t, false)
+	testShortReorgedSnapSyncingRepair(t, false)
 }
-func TestShortReorgedFastSyncingRepairWithSnapshots(t *testing.T) {
+func TestShortReorgedSnapSyncingRepairWithSnapshots(t *testing.T) {
-	testShortReorgedFastSyncingRepair(t, true)
+	testShortReorgedSnapSyncingRepair(t, true)
 }
 
-func testShortReorgedFastSyncingRepair(t *testing.T, snapshots bool) {
+func testShortReorgedSnapSyncingRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10
@@ -656,14 +656,14 @@ func testLongDeepRepair(t *testing.T, snapshots bool) {
 // sync pivot point - newer than the ancient limit - was already committed, after
 // which the process crashed. In this case we expect the chain to be rolled back
 // to the committed block, with everything afterwads kept as fast sync data.
-func TestLongFastSyncedShallowRepair(t *testing.T) {
+func TestLongSnapSyncedShallowRepair(t *testing.T) {
-	testLongFastSyncedShallowRepair(t, false)
+	testLongSnapSyncedShallowRepair(t, false)
 }
-func TestLongFastSyncedShallowRepairWithSnapshots(t *testing.T) {
+func TestLongSnapSyncedShallowRepairWithSnapshots(t *testing.T) {
-	testLongFastSyncedShallowRepair(t, true)
+	testLongSnapSyncedShallowRepair(t, true)
 }
 
-func testLongFastSyncedShallowRepair(t *testing.T, snapshots bool) {
+func testLongSnapSyncedShallowRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//
@@ -705,10 +705,10 @@ func testLongFastSyncedShallowRepair(t *testing.T, snapshots bool) {
 // sync pivot point - older than the ancient limit - was already committed, after
 // which the process crashed. In this case we expect the chain to be rolled back
 // to the committed block, with everything afterwads deleted.
-func TestLongFastSyncedDeepRepair(t *testing.T)              { testLongFastSyncedDeepRepair(t, false) }
+func TestLongSnapSyncedDeepRepair(t *testing.T)              { testLongSnapSyncedDeepRepair(t, false) }
-func TestLongFastSyncedDeepRepairWithSnapshots(t *testing.T) { testLongFastSyncedDeepRepair(t, true) }
+func TestLongSnapSyncedDeepRepairWithSnapshots(t *testing.T) { testLongSnapSyncedDeepRepair(t, true) }
 
-func testLongFastSyncedDeepRepair(t *testing.T, snapshots bool) {
+func testLongSnapSyncedDeepRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//
@@ -750,14 +750,14 @@ func testLongFastSyncedDeepRepair(t *testing.T, snapshots bool) {
 // process crashed. In this case we expect the chain to detect that it was fast
 // syncing and not delete anything, since we can just pick up directly where we
 // left off.
-func TestLongFastSyncingShallowRepair(t *testing.T) {
+func TestLongSnapSyncingShallowRepair(t *testing.T) {
-	testLongFastSyncingShallowRepair(t, false)
+	testLongSnapSyncingShallowRepair(t, false)
 }
-func TestLongFastSyncingShallowRepairWithSnapshots(t *testing.T) {
+func TestLongSnapSyncingShallowRepairWithSnapshots(t *testing.T) {
-	testLongFastSyncingShallowRepair(t, true)
+	testLongSnapSyncingShallowRepair(t, true)
 }
 
-func testLongFastSyncingShallowRepair(t *testing.T, snapshots bool) {
+func testLongSnapSyncingShallowRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//
@@ -800,10 +800,10 @@ func testLongFastSyncingShallowRepair(t *testing.T, snapshots bool) {
 // process crashed. In this case we expect the chain to detect that it was fast
 // syncing and not delete anything, since we can just pick up directly where we
 // left off.
-func TestLongFastSyncingDeepRepair(t *testing.T)              { testLongFastSyncingDeepRepair(t, false) }
+func TestLongSnapSyncingDeepRepair(t *testing.T)              { testLongSnapSyncingDeepRepair(t, false) }
-func TestLongFastSyncingDeepRepairWithSnapshots(t *testing.T) { testLongFastSyncingDeepRepair(t, true) }
+func TestLongSnapSyncingDeepRepairWithSnapshots(t *testing.T) { testLongSnapSyncingDeepRepair(t, true) }
 
-func testLongFastSyncingDeepRepair(t *testing.T, snapshots bool) {
+func testLongSnapSyncingDeepRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//
@@ -946,14 +946,14 @@ func testLongOldForkedDeepRepair(t *testing.T, snapshots bool) {
 // the side chain is below the committed block. In this case we expect the chain
 // to be rolled back to the committed block, with everything afterwads kept as
 // fast sync data; the side chain completely nuked by the freezer.
-func TestLongOldForkedFastSyncedShallowRepair(t *testing.T) {
+func TestLongOldForkedSnapSyncedShallowRepair(t *testing.T) {
-	testLongOldForkedFastSyncedShallowRepair(t, false)
+	testLongOldForkedSnapSyncedShallowRepair(t, false)
 }
-func TestLongOldForkedFastSyncedShallowRepairWithSnapshots(t *testing.T) {
+func TestLongOldForkedSnapSyncedShallowRepairWithSnapshots(t *testing.T) {
-	testLongOldForkedFastSyncedShallowRepair(t, true)
+	testLongOldForkedSnapSyncedShallowRepair(t, true)
 }
 
-func testLongOldForkedFastSyncedShallowRepair(t *testing.T, snapshots bool) {
+func testLongOldForkedSnapSyncedShallowRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3
@@ -998,14 +998,14 @@ func testLongOldForkedFastSyncedShallowRepair(t *testing.T, snapshots bool) {
 // the side chain is below the committed block. In this case we expect the canonical
 // chain to be rolled back to the committed block, with everything afterwads deleted;
 // the side chain completely nuked by the freezer.
-func TestLongOldForkedFastSyncedDeepRepair(t *testing.T) {
+func TestLongOldForkedSnapSyncedDeepRepair(t *testing.T) {
-	testLongOldForkedFastSyncedDeepRepair(t, false)
+	testLongOldForkedSnapSyncedDeepRepair(t, false)
 }
-func TestLongOldForkedFastSyncedDeepRepairWithSnapshots(t *testing.T) {
+func TestLongOldForkedSnapSyncedDeepRepairWithSnapshots(t *testing.T) {
-	testLongOldForkedFastSyncedDeepRepair(t, true)
+	testLongOldForkedSnapSyncedDeepRepair(t, true)
 }
 
-func testLongOldForkedFastSyncedDeepRepair(t *testing.T, snapshots bool) {
+func testLongOldForkedSnapSyncedDeepRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3
@@ -1049,14 +1049,14 @@ func testLongOldForkedFastSyncedDeepRepair(t *testing.T, snapshots bool) {
 // chain is below the committed block. In this case we expect the chain to detect
 // that it was fast syncing and not delete anything. The side chain is completely
 // nuked by the freezer.
-func TestLongOldForkedFastSyncingShallowRepair(t *testing.T) {
+func TestLongOldForkedSnapSyncingShallowRepair(t *testing.T) {
-	testLongOldForkedFastSyncingShallowRepair(t, false)
+	testLongOldForkedSnapSyncingShallowRepair(t, false)
 }
-func TestLongOldForkedFastSyncingShallowRepairWithSnapshots(t *testing.T) {
+func TestLongOldForkedSnapSyncingShallowRepairWithSnapshots(t *testing.T) {
-	testLongOldForkedFastSyncingShallowRepair(t, true)
+	testLongOldForkedSnapSyncingShallowRepair(t, true)
 }
 
-func testLongOldForkedFastSyncingShallowRepair(t *testing.T, snapshots bool) {
+func testLongOldForkedSnapSyncingShallowRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3
@@ -1101,14 +1101,14 @@ func testLongOldForkedFastSyncingShallowRepair(t *testing.T, snapshots bool) {
 // chain is below the committed block. In this case we expect the chain to detect
 // that it was fast syncing and not delete anything. The side chain is completely
 // nuked by the freezer.
-func TestLongOldForkedFastSyncingDeepRepair(t *testing.T) {
+func TestLongOldForkedSnapSyncingDeepRepair(t *testing.T) {
-	testLongOldForkedFastSyncingDeepRepair(t, false)
+	testLongOldForkedSnapSyncingDeepRepair(t, false)
 }
-func TestLongOldForkedFastSyncingDeepRepairWithSnapshots(t *testing.T) {
+func TestLongOldForkedSnapSyncingDeepRepairWithSnapshots(t *testing.T) {
-	testLongOldForkedFastSyncingDeepRepair(t, true)
+	testLongOldForkedSnapSyncingDeepRepair(t, true)
 }
 
-func testLongOldForkedFastSyncingDeepRepair(t *testing.T, snapshots bool) {
+func testLongOldForkedSnapSyncingDeepRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3
@@ -1252,14 +1252,14 @@ func testLongNewerForkedDeepRepair(t *testing.T, snapshots bool) {
 // the side chain is above the committed block. In this case we expect the chain
 // to be rolled back to the committed block, with everything afterwads kept as fast
 // sync data; the side chain completely nuked by the freezer.
-func TestLongNewerForkedFastSyncedShallowRepair(t *testing.T) {
+func TestLongNewerForkedSnapSyncedShallowRepair(t *testing.T) {
-	testLongNewerForkedFastSyncedShallowRepair(t, false)
+	testLongNewerForkedSnapSyncedShallowRepair(t, false)
 }
-func TestLongNewerForkedFastSyncedShallowRepairWithSnapshots(t *testing.T) {
+func TestLongNewerForkedSnapSyncedShallowRepairWithSnapshots(t *testing.T) {
-	testLongNewerForkedFastSyncedShallowRepair(t, true)
+	testLongNewerForkedSnapSyncedShallowRepair(t, true)
 }
 
-func testLongNewerForkedFastSyncedShallowRepair(t *testing.T, snapshots bool) {
+func testLongNewerForkedSnapSyncedShallowRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12
@@ -1304,14 +1304,14 @@ func testLongNewerForkedFastSyncedShallowRepair(t *testing.T, snapshots bool) {
 // the side chain is above the committed block. In this case we expect the canonical
 // chain to be rolled back to the committed block, with everything afterwads deleted;
 // the side chain completely nuked by the freezer.
-func TestLongNewerForkedFastSyncedDeepRepair(t *testing.T) {
+func TestLongNewerForkedSnapSyncedDeepRepair(t *testing.T) {
-	testLongNewerForkedFastSyncedDeepRepair(t, false)
+	testLongNewerForkedSnapSyncedDeepRepair(t, false)
 }
-func TestLongNewerForkedFastSyncedDeepRepairWithSnapshots(t *testing.T) {
+func TestLongNewerForkedSnapSyncedDeepRepairWithSnapshots(t *testing.T) {
-	testLongNewerForkedFastSyncedDeepRepair(t, true)
+	testLongNewerForkedSnapSyncedDeepRepair(t, true)
 }
 
-func testLongNewerForkedFastSyncedDeepRepair(t *testing.T, snapshots bool) {
+func testLongNewerForkedSnapSyncedDeepRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12
@@ -1355,14 +1355,14 @@ func testLongNewerForkedFastSyncedDeepRepair(t *testing.T, snapshots bool) {
 // chain is above the committed block. In this case we expect the chain to detect
 // that it was fast syncing and not delete anything. The side chain is completely
 // nuked by the freezer.
-func TestLongNewerForkedFastSyncingShallowRepair(t *testing.T) {
+func TestLongNewerForkedSnapSyncingShallowRepair(t *testing.T) {
-	testLongNewerForkedFastSyncingShallowRepair(t, false)
+	testLongNewerForkedSnapSyncingShallowRepair(t, false)
 }
-func TestLongNewerForkedFastSyncingShallowRepairWithSnapshots(t *testing.T) {
+func TestLongNewerForkedSnapSyncingShallowRepairWithSnapshots(t *testing.T) {
-	testLongNewerForkedFastSyncingShallowRepair(t, true)
+	testLongNewerForkedSnapSyncingShallowRepair(t, true)
 }
 
-func testLongNewerForkedFastSyncingShallowRepair(t *testing.T, snapshots bool) {
+func testLongNewerForkedSnapSyncingShallowRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12
@@ -1407,14 +1407,14 @@ func testLongNewerForkedFastSyncingShallowRepair(t *testing.T, snapshots bool) {
 // chain is above the committed block. In this case we expect the chain to detect
 // that it was fast syncing and not delete anything. The side chain is completely
 // nuked by the freezer.
-func TestLongNewerForkedFastSyncingDeepRepair(t *testing.T) {
+func TestLongNewerForkedSnapSyncingDeepRepair(t *testing.T) {
-	testLongNewerForkedFastSyncingDeepRepair(t, false)
+	testLongNewerForkedSnapSyncingDeepRepair(t, false)
 }
-func TestLongNewerForkedFastSyncingDeepRepairWithSnapshots(t *testing.T) {
+func TestLongNewerForkedSnapSyncingDeepRepairWithSnapshots(t *testing.T) {
-	testLongNewerForkedFastSyncingDeepRepair(t, true)
+	testLongNewerForkedSnapSyncingDeepRepair(t, true)
 }
 
-func testLongNewerForkedFastSyncingDeepRepair(t *testing.T, snapshots bool) {
+func testLongNewerForkedSnapSyncingDeepRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12
@@ -1552,14 +1552,14 @@ func testLongReorgedDeepRepair(t *testing.T, snapshots bool) {
 // expect the chain to be rolled back to the committed block, with everything
 // afterwads kept as fast sync data. The side chain completely nuked by the
 // freezer.
-func TestLongReorgedFastSyncedShallowRepair(t *testing.T) {
+func TestLongReorgedSnapSyncedShallowRepair(t *testing.T) {
-	testLongReorgedFastSyncedShallowRepair(t, false)
+	testLongReorgedSnapSyncedShallowRepair(t, false)
 }
-func TestLongReorgedFastSyncedShallowRepairWithSnapshots(t *testing.T) {
+func TestLongReorgedSnapSyncedShallowRepairWithSnapshots(t *testing.T) {
-	testLongReorgedFastSyncedShallowRepair(t, true)
+	testLongReorgedSnapSyncedShallowRepair(t, true)
 }
 
-func testLongReorgedFastSyncedShallowRepair(t *testing.T, snapshots bool) {
+func testLongReorgedSnapSyncedShallowRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12->S13->S14->S15->S16->S17->S18->S19->S20->S21->S22->S23->S24->S25->S26
@@ -1603,14 +1603,14 @@ func testLongReorgedFastSyncedShallowRepair(t *testing.T, snapshots bool) {
 // was already committed to disk and then the process crashed. In this case we
 // expect the canonical chains to be rolled back to the committed block, with
 // everything afterwads deleted. The side chain completely nuked by the freezer.
-func TestLongReorgedFastSyncedDeepRepair(t *testing.T) {
+func TestLongReorgedSnapSyncedDeepRepair(t *testing.T) {
-	testLongReorgedFastSyncedDeepRepair(t, false)
+	testLongReorgedSnapSyncedDeepRepair(t, false)
 }
-func TestLongReorgedFastSyncedDeepRepairWithSnapshots(t *testing.T) {
+func TestLongReorgedSnapSyncedDeepRepairWithSnapshots(t *testing.T) {
-	testLongReorgedFastSyncedDeepRepair(t, true)
+	testLongReorgedSnapSyncedDeepRepair(t, true)
 }
 
-func testLongReorgedFastSyncedDeepRepair(t *testing.T, snapshots bool) {
+func testLongReorgedSnapSyncedDeepRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12->S13->S14->S15->S16->S17->S18->S19->S20->S21->S22->S23->S24->S25->S26
@@ -1653,14 +1653,14 @@ func testLongReorgedFastSyncedDeepRepair(t *testing.T, snapshots bool) {
 // was not yet committed, but the process crashed. In this case we expect the
 // chain to detect that it was fast syncing and not delete anything, since we
 // can just pick up directly where we left off.
-func TestLongReorgedFastSyncingShallowRepair(t *testing.T) {
+func TestLongReorgedSnapSyncingShallowRepair(t *testing.T) {
-	testLongReorgedFastSyncingShallowRepair(t, false)
+	testLongReorgedSnapSyncingShallowRepair(t, false)
 }
-func TestLongReorgedFastSyncingShallowRepairWithSnapshots(t *testing.T) {
+func TestLongReorgedSnapSyncingShallowRepairWithSnapshots(t *testing.T) {
-	testLongReorgedFastSyncingShallowRepair(t, true)
+	testLongReorgedSnapSyncingShallowRepair(t, true)
 }
 
-func testLongReorgedFastSyncingShallowRepair(t *testing.T, snapshots bool) {
+func testLongReorgedSnapSyncingShallowRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12->S13->S14->S15->S16->S17->S18->S19->S20->S21->S22->S23->S24->S25->S26
@@ -1704,14 +1704,14 @@ func testLongReorgedFastSyncingShallowRepair(t *testing.T, snapshots bool) {
 // was not yet committed, but the process crashed. In this case we expect the
 // chain to detect that it was fast syncing and not delete anything, since we
 // can just pick up directly where we left off.
-func TestLongReorgedFastSyncingDeepRepair(t *testing.T) {
+func TestLongReorgedSnapSyncingDeepRepair(t *testing.T) {
-	testLongReorgedFastSyncingDeepRepair(t, false)
+	testLongReorgedSnapSyncingDeepRepair(t, false)
 }
-func TestLongReorgedFastSyncingDeepRepairWithSnapshots(t *testing.T) {
+func TestLongReorgedSnapSyncingDeepRepairWithSnapshots(t *testing.T) {
-	testLongReorgedFastSyncingDeepRepair(t, true)
+	testLongReorgedSnapSyncingDeepRepair(t, true)
 }
 
-func testLongReorgedFastSyncingDeepRepair(t *testing.T, snapshots bool) {
+func testLongReorgedSnapSyncingDeepRepair(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12->S13->S14->S15->S16->S17->S18->S19->S20->S21->S22->S23->S24->S25->S26

core/blockchain_sethead_test.go

@@ -194,10 +194,10 @@ func testShortSetHead(t *testing.T, snapshots bool) {
 // Everything above the sethead point should be deleted. In between the committed
 // block and the requested head the data can remain as "fast sync" data to avoid
 // redownloading it.
-func TestShortFastSyncedSetHead(t *testing.T)              { testShortFastSyncedSetHead(t, false) }
+func TestShortSnapSyncedSetHead(t *testing.T)              { testShortSnapSyncedSetHead(t, false) }
-func TestShortFastSyncedSetHeadWithSnapshots(t *testing.T) { testShortFastSyncedSetHead(t, true) }
+func TestShortSnapSyncedSetHeadWithSnapshots(t *testing.T) { testShortSnapSyncedSetHead(t, true) }
 
-func testShortFastSyncedSetHead(t *testing.T, snapshots bool) {
+func testShortSnapSyncedSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//
@@ -236,10 +236,10 @@ func testShortFastSyncedSetHead(t *testing.T, snapshots bool) {
 // detect that it was fast syncing and delete everything from the new head, since
 // we can just pick up fast syncing from there. The head full block should be set
 // to the genesis.
-func TestShortFastSyncingSetHead(t *testing.T)              { testShortFastSyncingSetHead(t, false) }
+func TestShortSnapSyncingSetHead(t *testing.T)              { testShortSnapSyncingSetHead(t, false) }
-func TestShortFastSyncingSetHeadWithSnapshots(t *testing.T) { testShortFastSyncingSetHead(t, true) }
+func TestShortSnapSyncingSetHeadWithSnapshots(t *testing.T) { testShortSnapSyncingSetHead(t, true) }
 
-func testShortFastSyncingSetHead(t *testing.T, snapshots bool) {
+func testShortSnapSyncingSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//
@@ -326,14 +326,14 @@ func testShortOldForkedSetHead(t *testing.T, snapshots bool) {
 // block. Everything above the sethead point should be deleted. In between the
 // committed block and the requested head the data can remain as "fast sync" data
 // to avoid redownloading it. The side chain should be left alone as it was shorter.
-func TestShortOldForkedFastSyncedSetHead(t *testing.T) {
+func TestShortOldForkedSnapSyncedSetHead(t *testing.T) {
-	testShortOldForkedFastSyncedSetHead(t, false)
+	testShortOldForkedSnapSyncedSetHead(t, false)
 }
-func TestShortOldForkedFastSyncedSetHeadWithSnapshots(t *testing.T) {
+func TestShortOldForkedSnapSyncedSetHeadWithSnapshots(t *testing.T) {
-	testShortOldForkedFastSyncedSetHead(t, true)
+	testShortOldForkedSnapSyncedSetHead(t, true)
 }
 
-func testShortOldForkedFastSyncedSetHead(t *testing.T, snapshots bool) {
+func testShortOldForkedSnapSyncedSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3
@@ -375,14 +375,14 @@ func testShortOldForkedFastSyncedSetHead(t *testing.T, snapshots bool) {
 // the chain to detect that it was fast syncing and delete everything from the new
 // head, since we can just pick up fast syncing from there. The head full block
 // should be set to the genesis.
-func TestShortOldForkedFastSyncingSetHead(t *testing.T) {
+func TestShortOldForkedSnapSyncingSetHead(t *testing.T) {
-	testShortOldForkedFastSyncingSetHead(t, false)
+	testShortOldForkedSnapSyncingSetHead(t, false)
 }
-func TestShortOldForkedFastSyncingSetHeadWithSnapshots(t *testing.T) {
+func TestShortOldForkedSnapSyncingSetHeadWithSnapshots(t *testing.T) {
-	testShortOldForkedFastSyncingSetHead(t, true)
+	testShortOldForkedSnapSyncingSetHead(t, true)
 }
 
-func testShortOldForkedFastSyncingSetHead(t *testing.T, snapshots bool) {
+func testShortOldForkedSnapSyncingSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3
@@ -478,14 +478,14 @@ func testShortNewlyForkedSetHead(t *testing.T, snapshots bool) {
 // The side chain could be left to be if the fork point was before the new head
 // we are deleting to, but it would be exceedingly hard to detect that case and
 // properly handle it, so we'll trade extra work in exchange for simpler code.
-func TestShortNewlyForkedFastSyncedSetHead(t *testing.T) {
+func TestShortNewlyForkedSnapSyncedSetHead(t *testing.T) {
-	testShortNewlyForkedFastSyncedSetHead(t, false)
+	testShortNewlyForkedSnapSyncedSetHead(t, false)
 }
-func TestShortNewlyForkedFastSyncedSetHeadWithSnapshots(t *testing.T) {
+func TestShortNewlyForkedSnapSyncedSetHeadWithSnapshots(t *testing.T) {
-	testShortNewlyForkedFastSyncedSetHead(t, true)
+	testShortNewlyForkedSnapSyncedSetHead(t, true)
 }
 
-func testShortNewlyForkedFastSyncedSetHead(t *testing.T, snapshots bool) {
+func testShortNewlyForkedSnapSyncedSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8
@@ -531,14 +531,14 @@ func testShortNewlyForkedFastSyncedSetHead(t *testing.T, snapshots bool) {
 // The side chain could be left to be if the fork point was before the new head
 // we are deleting to, but it would be exceedingly hard to detect that case and
 // properly handle it, so we'll trade extra work in exchange for simpler code.
-func TestShortNewlyForkedFastSyncingSetHead(t *testing.T) {
+func TestShortNewlyForkedSnapSyncingSetHead(t *testing.T) {
-	testShortNewlyForkedFastSyncingSetHead(t, false)
+	testShortNewlyForkedSnapSyncingSetHead(t, false)
 }
-func TestShortNewlyForkedFastSyncingSetHeadWithSnapshots(t *testing.T) {
+func TestShortNewlyForkedSnapSyncingSetHeadWithSnapshots(t *testing.T) {
-	testShortNewlyForkedFastSyncingSetHead(t, true)
+	testShortNewlyForkedSnapSyncingSetHead(t, true)
 }
 
-func testShortNewlyForkedFastSyncingSetHead(t *testing.T, snapshots bool) {
+func testShortNewlyForkedSnapSyncingSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8
@@ -634,14 +634,14 @@ func testShortReorgedSetHead(t *testing.T, snapshots bool) {
 // The side chain could be left to be if the fork point was before the new head
 // we are deleting to, but it would be exceedingly hard to detect that case and
 // properly handle it, so we'll trade extra work in exchange for simpler code.
-func TestShortReorgedFastSyncedSetHead(t *testing.T) {
+func TestShortReorgedSnapSyncedSetHead(t *testing.T) {
-	testShortReorgedFastSyncedSetHead(t, false)
+	testShortReorgedSnapSyncedSetHead(t, false)
 }
-func TestShortReorgedFastSyncedSetHeadWithSnapshots(t *testing.T) {
+func TestShortReorgedSnapSyncedSetHeadWithSnapshots(t *testing.T) {
-	testShortReorgedFastSyncedSetHead(t, true)
+	testShortReorgedSnapSyncedSetHead(t, true)
 }
 
-func testShortReorgedFastSyncedSetHead(t *testing.T, snapshots bool) {
+func testShortReorgedSnapSyncedSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10
@@ -686,14 +686,14 @@ func testShortReorgedFastSyncedSetHead(t *testing.T, snapshots bool) {
 // The side chain could be left to be if the fork point was before the new head
 // we are deleting to, but it would be exceedingly hard to detect that case and
 // properly handle it, so we'll trade extra work in exchange for simpler code.
-func TestShortReorgedFastSyncingSetHead(t *testing.T) {
+func TestShortReorgedSnapSyncingSetHead(t *testing.T) {
-	testShortReorgedFastSyncingSetHead(t, false)
+	testShortReorgedSnapSyncingSetHead(t, false)
 }
-func TestShortReorgedFastSyncingSetHeadWithSnapshots(t *testing.T) {
+func TestShortReorgedSnapSyncingSetHeadWithSnapshots(t *testing.T) {
-	testShortReorgedFastSyncingSetHead(t, true)
+	testShortReorgedSnapSyncingSetHead(t, true)
 }
 
-func testShortReorgedFastSyncingSetHead(t *testing.T, snapshots bool) {
+func testShortReorgedSnapSyncingSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10
@@ -829,14 +829,14 @@ func testLongDeepSetHead(t *testing.T, snapshots bool) {
 // back to the committed block. Everything above the sethead point should be
 // deleted. In between the committed block and the requested head the data can
 // remain as "fast sync" data to avoid redownloading it.
-func TestLongFastSyncedShallowSetHead(t *testing.T) {
+func TestLongSnapSyncedShallowSetHead(t *testing.T) {
-	testLongFastSyncedShallowSetHead(t, false)
+	testLongSnapSyncedShallowSetHead(t, false)
 }
-func TestLongFastSyncedShallowSetHeadWithSnapshots(t *testing.T) {
+func TestLongSnapSyncedShallowSetHeadWithSnapshots(t *testing.T) {
-	testLongFastSyncedShallowSetHead(t, true)
+	testLongSnapSyncedShallowSetHead(t, true)
 }
 
-func testLongFastSyncedShallowSetHead(t *testing.T, snapshots bool) {
+func testLongSnapSyncedShallowSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//
@@ -880,10 +880,10 @@ func testLongFastSyncedShallowSetHead(t *testing.T, snapshots bool) {
 // which sethead was called. In this case we expect the full chain to be rolled
 // back to the committed block. Since the ancient limit was underflown, everything
 // needs to be deleted onwards to avoid creating a gap.
-func TestLongFastSyncedDeepSetHead(t *testing.T)              { testLongFastSyncedDeepSetHead(t, false) }
+func TestLongSnapSyncedDeepSetHead(t *testing.T)              { testLongSnapSyncedDeepSetHead(t, false) }
-func TestLongFastSyncedDeepSetHeadWithSnapshots(t *testing.T) { testLongFastSyncedDeepSetHead(t, true) }
+func TestLongSnapSyncedDeepSetHeadWithSnapshots(t *testing.T) { testLongSnapSyncedDeepSetHead(t, true) }
 
-func testLongFastSyncedDeepSetHead(t *testing.T, snapshots bool) {
+func testLongSnapSyncedDeepSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//
@@ -926,14 +926,14 @@ func testLongFastSyncedDeepSetHead(t *testing.T, snapshots bool) {
 // sethead was called. In this case we expect the chain to detect that it was fast
 // syncing and delete everything from the new head, since we can just pick up fast
 // syncing from there.
-func TestLongFastSyncingShallowSetHead(t *testing.T) {
+func TestLongSnapSyncingShallowSetHead(t *testing.T) {
-	testLongFastSyncingShallowSetHead(t, false)
+	testLongSnapSyncingShallowSetHead(t, false)
 }
-func TestLongFastSyncingShallowSetHeadWithSnapshots(t *testing.T) {
+func TestLongSnapSyncingShallowSetHeadWithSnapshots(t *testing.T) {
-	testLongFastSyncingShallowSetHead(t, true)
+	testLongSnapSyncingShallowSetHead(t, true)
 }
 
-func testLongFastSyncingShallowSetHead(t *testing.T, snapshots bool) {
+func testLongSnapSyncingShallowSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//
@@ -977,14 +977,14 @@ func testLongFastSyncingShallowSetHead(t *testing.T, snapshots bool) {
 // sethead was called. In this case we expect the chain to detect that it was fast
 // syncing and delete everything from the new head, since we can just pick up fast
 // syncing from there.
-func TestLongFastSyncingDeepSetHead(t *testing.T) {
+func TestLongSnapSyncingDeepSetHead(t *testing.T) {
-	testLongFastSyncingDeepSetHead(t, false)
+	testLongSnapSyncingDeepSetHead(t, false)
 }
-func TestLongFastSyncingDeepSetHeadWithSnapshots(t *testing.T) {
+func TestLongSnapSyncingDeepSetHeadWithSnapshots(t *testing.T) {
-	testLongFastSyncingDeepSetHead(t, true)
+	testLongSnapSyncingDeepSetHead(t, true)
 }
 
-func testLongFastSyncingDeepSetHead(t *testing.T, snapshots bool) {
+func testLongSnapSyncingDeepSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//
@@ -1132,14 +1132,14 @@ func testLongOldForkedDeepSetHead(t *testing.T, snapshots bool) {
 // sethead point should be deleted. In between the committed block and the
 // requested head the data can remain as "fast sync" data to avoid redownloading
 // it. The side chain is nuked by the freezer.
-func TestLongOldForkedFastSyncedShallowSetHead(t *testing.T) {
+func TestLongOldForkedSnapSyncedShallowSetHead(t *testing.T) {
-	testLongOldForkedFastSyncedShallowSetHead(t, false)
+	testLongOldForkedSnapSyncedShallowSetHead(t, false)
 }
-func TestLongOldForkedFastSyncedShallowSetHeadWithSnapshots(t *testing.T) {
+func TestLongOldForkedSnapSyncedShallowSetHeadWithSnapshots(t *testing.T) {
-	testLongOldForkedFastSyncedShallowSetHead(t, true)
+	testLongOldForkedSnapSyncedShallowSetHead(t, true)
 }
 
-func testLongOldForkedFastSyncedShallowSetHead(t *testing.T, snapshots bool) {
+func testLongOldForkedSnapSyncedShallowSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3
@@ -1186,14 +1186,14 @@ func testLongOldForkedFastSyncedShallowSetHead(t *testing.T, snapshots bool) {
 // full chain to be rolled back to the committed block. Since the ancient limit was
 // underflown, everything needs to be deleted onwards to avoid creating a gap. The
 // side chain is nuked by the freezer.
-func TestLongOldForkedFastSyncedDeepSetHead(t *testing.T) {
+func TestLongOldForkedSnapSyncedDeepSetHead(t *testing.T) {
-	testLongOldForkedFastSyncedDeepSetHead(t, false)
+	testLongOldForkedSnapSyncedDeepSetHead(t, false)
 }
-func TestLongOldForkedFastSyncedDeepSetHeadWithSnapshots(t *testing.T) {
+func TestLongOldForkedSnapSyncedDeepSetHeadWithSnapshots(t *testing.T) {
-	testLongOldForkedFastSyncedDeepSetHead(t, true)
+	testLongOldForkedSnapSyncedDeepSetHead(t, true)
 }
 
-func testLongOldForkedFastSyncedDeepSetHead(t *testing.T, snapshots bool) {
+func testLongOldForkedSnapSyncedDeepSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3
@@ -1239,14 +1239,14 @@ func testLongOldForkedFastSyncedDeepSetHead(t *testing.T, snapshots bool) {
 // that it was fast syncing and delete everything from the new head, since we can
 // just pick up fast syncing from there. The side chain is completely nuked by the
 // freezer.
-func TestLongOldForkedFastSyncingShallowSetHead(t *testing.T) {
+func TestLongOldForkedSnapSyncingShallowSetHead(t *testing.T) {
-	testLongOldForkedFastSyncingShallowSetHead(t, false)
+	testLongOldForkedSnapSyncingShallowSetHead(t, false)
 }
-func TestLongOldForkedFastSyncingShallowSetHeadWithSnapshots(t *testing.T) {
+func TestLongOldForkedSnapSyncingShallowSetHeadWithSnapshots(t *testing.T) {
-	testLongOldForkedFastSyncingShallowSetHead(t, true)
+	testLongOldForkedSnapSyncingShallowSetHead(t, true)
 }
 
-func testLongOldForkedFastSyncingShallowSetHead(t *testing.T, snapshots bool) {
+func testLongOldForkedSnapSyncingShallowSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3
@@ -1293,14 +1293,14 @@ func testLongOldForkedFastSyncingShallowSetHead(t *testing.T, snapshots bool) {
 // that it was fast syncing and delete everything from the new head, since we can
 // just pick up fast syncing from there. The side chain is completely nuked by the
 // freezer.
-func TestLongOldForkedFastSyncingDeepSetHead(t *testing.T) {
+func TestLongOldForkedSnapSyncingDeepSetHead(t *testing.T) {
-	testLongOldForkedFastSyncingDeepSetHead(t, false)
+	testLongOldForkedSnapSyncingDeepSetHead(t, false)
 }
-func TestLongOldForkedFastSyncingDeepSetHeadWithSnapshots(t *testing.T) {
+func TestLongOldForkedSnapSyncingDeepSetHeadWithSnapshots(t *testing.T) {
-	testLongOldForkedFastSyncingDeepSetHead(t, true)
+	testLongOldForkedSnapSyncingDeepSetHead(t, true)
 }
 
-func testLongOldForkedFastSyncingDeepSetHead(t *testing.T, snapshots bool) {
+func testLongOldForkedSnapSyncingDeepSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3
@@ -1446,15 +1446,15 @@ func testLongNewerForkedDeepSetHead(t *testing.T, snapshots bool) {
 // side chain, where the fast sync pivot point - newer than the ancient limit -
 // was already committed to disk and then sethead was called. In this test scenario
 // the side chain is above the committed block. In this case the freezer will delete
-// the sidechain since it's dangling, reverting to TestLongFastSyncedShallowSetHead.
+// the sidechain since it's dangling, reverting to TestLongSnapSyncedShallowSetHead.
-func TestLongNewerForkedFastSyncedShallowSetHead(t *testing.T) {
+func TestLongNewerForkedSnapSyncedShallowSetHead(t *testing.T) {
-	testLongNewerForkedFastSyncedShallowSetHead(t, false)
+	testLongNewerForkedSnapSyncedShallowSetHead(t, false)
 }
-func TestLongNewerForkedFastSyncedShallowSetHeadWithSnapshots(t *testing.T) {
+func TestLongNewerForkedSnapSyncedShallowSetHeadWithSnapshots(t *testing.T) {
-	testLongNewerForkedFastSyncedShallowSetHead(t, true)
+	testLongNewerForkedSnapSyncedShallowSetHead(t, true)
 }
 
-func testLongNewerForkedFastSyncedShallowSetHead(t *testing.T, snapshots bool) {
+func testLongNewerForkedSnapSyncedShallowSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12
@@ -1498,15 +1498,15 @@ func testLongNewerForkedFastSyncedShallowSetHead(t *testing.T, snapshots bool) {
 // side chain, where the fast sync pivot point - older than the ancient limit -
 // was already committed to disk and then sethead was called. In this test scenario
 // the side chain is above the committed block. In this case the freezer will delete
-// the sidechain since it's dangling, reverting to TestLongFastSyncedDeepSetHead.
+// the sidechain since it's dangling, reverting to TestLongSnapSyncedDeepSetHead.
-func TestLongNewerForkedFastSyncedDeepSetHead(t *testing.T) {
+func TestLongNewerForkedSnapSyncedDeepSetHead(t *testing.T) {
-	testLongNewerForkedFastSyncedDeepSetHead(t, false)
+	testLongNewerForkedSnapSyncedDeepSetHead(t, false)
 }
-func TestLongNewerForkedFastSyncedDeepSetHeadWithSnapshots(t *testing.T) {
+func TestLongNewerForkedSnapSyncedDeepSetHeadWithSnapshots(t *testing.T) {
-	testLongNewerForkedFastSyncedDeepSetHead(t, true)
+	testLongNewerForkedSnapSyncedDeepSetHead(t, true)
 }
 
-func testLongNewerForkedFastSyncedDeepSetHead(t *testing.T, snapshots bool) {
+func testLongNewerForkedSnapSyncedDeepSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12
@@ -1549,15 +1549,15 @@ func testLongNewerForkedFastSyncedDeepSetHead(t *testing.T, snapshots bool) {
 // side chain, where the fast sync pivot point - newer than the ancient limit -
 // was not yet committed, but sethead was called. In this test scenario the side
 // chain is above the committed block. In this case the freezer will delete the
-// sidechain since it's dangling, reverting to TestLongFastSyncinghallowSetHead.
+// sidechain since it's dangling, reverting to TestLongSnapSyncinghallowSetHead.
-func TestLongNewerForkedFastSyncingShallowSetHead(t *testing.T) {
+func TestLongNewerForkedSnapSyncingShallowSetHead(t *testing.T) {
-	testLongNewerForkedFastSyncingShallowSetHead(t, false)
+	testLongNewerForkedSnapSyncingShallowSetHead(t, false)
 }
-func TestLongNewerForkedFastSyncingShallowSetHeadWithSnapshots(t *testing.T) {
+func TestLongNewerForkedSnapSyncingShallowSetHeadWithSnapshots(t *testing.T) {
-	testLongNewerForkedFastSyncingShallowSetHead(t, true)
+	testLongNewerForkedSnapSyncingShallowSetHead(t, true)
 }
 
-func testLongNewerForkedFastSyncingShallowSetHead(t *testing.T, snapshots bool) {
+func testLongNewerForkedSnapSyncingShallowSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12
@@ -1601,15 +1601,15 @@ func testLongNewerForkedFastSyncingShallowSetHead(t *testing.T, snapshots bool)
 // side chain, where the fast sync pivot point - older than the ancient limit -
 // was not yet committed, but sethead was called. In this test scenario the side
 // chain is above the committed block. In this case the freezer will delete the
-// sidechain since it's dangling, reverting to TestLongFastSyncingDeepSetHead.
+// sidechain since it's dangling, reverting to TestLongSnapSyncingDeepSetHead.
-func TestLongNewerForkedFastSyncingDeepSetHead(t *testing.T) {
+func TestLongNewerForkedSnapSyncingDeepSetHead(t *testing.T) {
-	testLongNewerForkedFastSyncingDeepSetHead(t, false)
+	testLongNewerForkedSnapSyncingDeepSetHead(t, false)
 }
-func TestLongNewerForkedFastSyncingDeepSetHeadWithSnapshots(t *testing.T) {
+func TestLongNewerForkedSnapSyncingDeepSetHeadWithSnapshots(t *testing.T) {
-	testLongNewerForkedFastSyncingDeepSetHead(t, true)
+	testLongNewerForkedSnapSyncingDeepSetHead(t, true)
 }
 
-func testLongNewerForkedFastSyncingDeepSetHead(t *testing.T, snapshots bool) {
+func testLongNewerForkedSnapSyncingDeepSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12
@@ -1745,15 +1745,15 @@ func testLongReorgedDeepSetHead(t *testing.T, snapshots bool) {
 // side chain, where the fast sync pivot point - newer than the ancient limit -
 // was already committed to disk and then sethead was called. In this case the
 // freezer will delete the sidechain since it's dangling, reverting to
-// TestLongFastSyncedShallowSetHead.
+// TestLongSnapSyncedShallowSetHead.
-func TestLongReorgedFastSyncedShallowSetHead(t *testing.T) {
+func TestLongReorgedSnapSyncedShallowSetHead(t *testing.T) {
-	testLongReorgedFastSyncedShallowSetHead(t, false)
+	testLongReorgedSnapSyncedShallowSetHead(t, false)
 }
-func TestLongReorgedFastSyncedShallowSetHeadWithSnapshots(t *testing.T) {
+func TestLongReorgedSnapSyncedShallowSetHeadWithSnapshots(t *testing.T) {
-	testLongReorgedFastSyncedShallowSetHead(t, true)
+	testLongReorgedSnapSyncedShallowSetHead(t, true)
 }
 
-func testLongReorgedFastSyncedShallowSetHead(t *testing.T, snapshots bool) {
+func testLongReorgedSnapSyncedShallowSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12->S13->S14->S15->S16->S17->S18->S19->S20->S21->S22->S23->S24->S25->S26
@@ -1797,15 +1797,15 @@ func testLongReorgedFastSyncedShallowSetHead(t *testing.T, snapshots bool) {
 // side chain, where the fast sync pivot point - older than the ancient limit -
 // was already committed to disk and then sethead was called. In this case the
 // freezer will delete the sidechain since it's dangling, reverting to
-// TestLongFastSyncedDeepSetHead.
+// TestLongSnapSyncedDeepSetHead.
-func TestLongReorgedFastSyncedDeepSetHead(t *testing.T) {
+func TestLongReorgedSnapSyncedDeepSetHead(t *testing.T) {
-	testLongReorgedFastSyncedDeepSetHead(t, false)
+	testLongReorgedSnapSyncedDeepSetHead(t, false)
 }
-func TestLongReorgedFastSyncedDeepSetHeadWithSnapshots(t *testing.T) {
+func TestLongReorgedSnapSyncedDeepSetHeadWithSnapshots(t *testing.T) {
-	testLongReorgedFastSyncedDeepSetHead(t, true)
+	testLongReorgedSnapSyncedDeepSetHead(t, true)
 }
 
-func testLongReorgedFastSyncedDeepSetHead(t *testing.T, snapshots bool) {
+func testLongReorgedSnapSyncedDeepSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12->S13->S14->S15->S16->S17->S18->S19->S20->S21->S22->S23->S24->S25->S26
@@ -1850,14 +1850,14 @@ func testLongReorgedFastSyncedDeepSetHead(t *testing.T, snapshots bool) {
 // chain to detect that it was fast syncing and delete everything from the new
 // head, since we can just pick up fast syncing from there. The side chain is
 // completely nuked by the freezer.
-func TestLongReorgedFastSyncingShallowSetHead(t *testing.T) {
+func TestLongReorgedSnapSyncingShallowSetHead(t *testing.T) {
-	testLongReorgedFastSyncingShallowSetHead(t, false)
+	testLongReorgedSnapSyncingShallowSetHead(t, false)
 }
-func TestLongReorgedFastSyncingShallowSetHeadWithSnapshots(t *testing.T) {
+func TestLongReorgedSnapSyncingShallowSetHeadWithSnapshots(t *testing.T) {
-	testLongReorgedFastSyncingShallowSetHead(t, true)
+	testLongReorgedSnapSyncingShallowSetHead(t, true)
 }
 
-func testLongReorgedFastSyncingShallowSetHead(t *testing.T, snapshots bool) {
+func testLongReorgedSnapSyncingShallowSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12->S13->S14->S15->S16->S17->S18->S19->S20->S21->S22->S23->S24->S25->S26
@@ -1903,14 +1903,14 @@ func testLongReorgedFastSyncingShallowSetHead(t *testing.T, snapshots bool) {
 // chain to detect that it was fast syncing and delete everything from the new
 // head, since we can just pick up fast syncing from there. The side chain is
 // completely nuked by the freezer.
-func TestLongReorgedFastSyncingDeepSetHead(t *testing.T) {
+func TestLongReorgedSnapSyncingDeepSetHead(t *testing.T) {
-	testLongReorgedFastSyncingDeepSetHead(t, false)
+	testLongReorgedSnapSyncingDeepSetHead(t, false)
 }
-func TestLongReorgedFastSyncingDeepSetHeadWithSnapshots(t *testing.T) {
+func TestLongReorgedSnapSyncingDeepSetHeadWithSnapshots(t *testing.T) {
-	testLongReorgedFastSyncingDeepSetHead(t, true)
+	testLongReorgedSnapSyncingDeepSetHead(t, true)
 }
 
-func testLongReorgedFastSyncingDeepSetHead(t *testing.T, snapshots bool) {
+func testLongReorgedSnapSyncingDeepSetHead(t *testing.T, snapshots bool) {
 	// Chain:
 	//   G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10->C11->C12->C13->C14->C15->C16->C17->C18->C19->C20->C21->C22->C23->C24 (HEAD)
 	//   └->S1->S2->S3->S4->S5->S6->S7->S8->S9->S10->S11->S12->S13->S14->S15->S16->S17->S18->S19->S20->S21->S22->S23->S24->S25->S26

core/blockchain_test.go

@@ -2637,7 +2637,7 @@ func TestTransactionIndices(t *testing.T) {
 	}
 }
 
-func TestSkipStaleTxIndicesInFastSync(t *testing.T) {
+func TestSkipStaleTxIndicesInSnapSync(t *testing.T) {
 	// Configure and generate a sample block chain
 	var (
 		gendb   = rawdb.NewMemoryDatabase()

core/chain_makers.go

@@ -155,6 +155,28 @@ func (b *BlockGen) TxNonce(addr common.Address) uint64 {
 
 // AddUncle adds an uncle header to the generated block.
 func (b *BlockGen) AddUncle(h *types.Header) {
+	// The uncle will have the same timestamp and auto-generated difficulty
+	h.Time = b.header.Time
+
+	var parent *types.Header
+	for i := b.i - 1; i >= 0; i-- {
+		if b.chain[i].Hash() == h.ParentHash {
+			parent = b.chain[i].Header()
+			break
+		}
+	}
+	chainreader := &fakeChainReader{config: b.config}
+	h.Difficulty = b.engine.CalcDifficulty(chainreader, b.header.Time, parent)
+
+	// The gas limit and price should be derived from the parent
+	h.GasLimit = parent.GasLimit
+	if b.config.IsLondon(h.Number) {
+		h.BaseFee = misc.CalcBaseFee(b.config, parent)
+		if !b.config.IsLondon(parent.Number) {
+			parentGasLimit := parent.GasLimit * params.ElasticityMultiplier
+			h.GasLimit = CalcGasLimit(parentGasLimit, parentGasLimit)
+		}
+	}
 	b.uncles = append(b.uncles, h)
 }
 

core/rawdb/accessors_chain.go

@@ -242,24 +242,6 @@ func WriteLastPivotNumber(db ethdb.KeyValueWriter, pivot uint64) {
 	}
 }
 
-// ReadFastTrieProgress retrieves the number of tries nodes fast synced to allow
-// reporting correct numbers across restarts.
-func ReadFastTrieProgress(db ethdb.KeyValueReader) uint64 {
-	data, _ := db.Get(fastTrieProgressKey)
-	if len(data) == 0 {
-		return 0
-	}
-	return new(big.Int).SetBytes(data).Uint64()
-}
-
-// WriteFastTrieProgress stores the fast sync trie process counter to support
-// retrieving it across restarts.
-func WriteFastTrieProgress(db ethdb.KeyValueWriter, count uint64) {
-	if err := db.Put(fastTrieProgressKey, new(big.Int).SetUint64(count).Bytes()); err != nil {
-		log.Crit("Failed to store fast sync trie progress", "err", err)
-	}
-}
-
 // ReadTxIndexTail retrieves the number of oldest indexed block
 // whose transaction indices has been indexed. If the corresponding entry
 // is non-existent in database it means the indexing has been finished.

core/rawdb/accessors_snapshot.go

@@ -208,11 +208,3 @@ func WriteSnapshotSyncStatus(db ethdb.KeyValueWriter, status []byte) {
 		log.Crit("Failed to store snapshot sync status", "err", err)
 	}
 }
-
-// DeleteSnapshotSyncStatus deletes the serialized sync status saved at the last
-// shutdown
-func DeleteSnapshotSyncStatus(db ethdb.KeyValueWriter) {
-	if err := db.Delete(snapshotSyncStatusKey); err != nil {
-		log.Crit("Failed to remove snapshot sync status", "err", err)
-	}
-}

eth/downloader/fetchers.go

@@ -0,0 +1,115 @@
+// Copyright 2021 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package downloader
+
+import (
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/eth/protocols/eth"
+)
+
+// fetchHeadersByHash is a blocking version of Peer.RequestHeadersByHash which
+// handles all the cancellation, interruption and timeout mechanisms of a data
+// retrieval to allow blocking API calls.
+func (d *Downloader) fetchHeadersByHash(p *peerConnection, hash common.Hash, amount int, skip int, reverse bool) ([]*types.Header, error) {
+	// Create the response sink and send the network request
+	start := time.Now()
+	resCh := make(chan *eth.Response)
+
+	req, err := p.peer.RequestHeadersByHash(hash, amount, skip, reverse, resCh)
+	if err != nil {
+		return nil, err
+	}
+	defer req.Close()
+
+	// Wait until the response arrives, the request is cancelled or times out
+	ttl := d.peers.rates.TargetTimeout()
+
+	timeoutTimer := time.NewTimer(ttl)
+	defer timeoutTimer.Stop()
+
+	select {
+	case <-d.cancelCh:
+		return nil, errCanceled
+
+	case <-timeoutTimer.C:
+		// Header retrieval timed out, update the metrics
+		p.log.Debug("Header request timed out", "elapsed", ttl)
+		headerTimeoutMeter.Mark(1)
+
+		return nil, errTimeout
+
+	case res := <-resCh:
+		// Headers successfully retrieved, update the metrics
+		headerReqTimer.Update(time.Since(start))
+		headerInMeter.Mark(int64(len(*res.Res.(*eth.BlockHeadersPacket))))
+
+		// Don't reject the packet even if it turns out to be bad, downloader will
+		// disconnect the peer on its own terms. Simply delivery the headers to
+		// be processed by the caller
+		res.Done <- nil
+
+		return *res.Res.(*eth.BlockHeadersPacket), nil
+	}
+}
+
+// fetchHeadersByNumber is a blocking version of Peer.RequestHeadersByNumber which
+// handles all the cancellation, interruption and timeout mechanisms of a data
+// retrieval to allow blocking API calls.
+func (d *Downloader) fetchHeadersByNumber(p *peerConnection, number uint64, amount int, skip int, reverse bool) ([]*types.Header, error) {
+	// Create the response sink and send the network request
+	start := time.Now()
+	resCh := make(chan *eth.Response)
+
+	req, err := p.peer.RequestHeadersByNumber(number, amount, skip, reverse, resCh)
+	if err != nil {
+		return nil, err
+	}
+	defer req.Close()
+
+	// Wait until the response arrives, the request is cancelled or times out
+	ttl := d.peers.rates.TargetTimeout()
+
+	timeoutTimer := time.NewTimer(ttl)
+	defer timeoutTimer.Stop()
+
+	select {
+	case <-d.cancelCh:
+		return nil, errCanceled
+
+	case <-timeoutTimer.C:
+		// Header retrieval timed out, update the metrics
+		p.log.Debug("Header request timed out", "elapsed", ttl)
+		headerTimeoutMeter.Mark(1)
+
+		return nil, errTimeout
+
+	case res := <-resCh:
+		// Headers successfully retrieved, update the metrics
+		headerReqTimer.Update(time.Since(start))
+		headerInMeter.Mark(int64(len(*res.Res.(*eth.BlockHeadersPacket))))
+
+		// Don't reject the packet even if it turns out to be bad, downloader will
+		// disconnect the peer on its own terms. Simply delivery the headers to
+		// be processed by the caller
+		res.Done <- nil
+
+		return *res.Res.(*eth.BlockHeadersPacket), nil
+	}
+}

eth/downloader/fetchers_concurrent.go

@@ -0,0 +1,381 @@
+// Copyright 2021 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package downloader
+
+import (
+	"errors"
+	"sort"
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/prque"
+	"github.com/ethereum/go-ethereum/eth/protocols/eth"
+	"github.com/ethereum/go-ethereum/log"
+)
+
+// timeoutGracePeriod is the amount of time to allow for a peer to deliver a
+// response to a locally already timed out request. Timeouts are not penalized
+// as a peer might be temporarily overloaded, however, they still must reply
+// to each request. Failing to do so is considered a protocol violation.
+var timeoutGracePeriod = 2 * time.Minute
+
+// typedQueue is an interface defining the adaptor needed to translate the type
+// specific downloader/queue schedulers into the type-agnostic general concurrent
+// fetcher algorithm calls.
+type typedQueue interface {
+	// waker returns a notification channel that gets pinged in case more fetches
+	// have been queued up, so the fetcher might assign it to idle peers.
+	waker() chan bool
+
+	// pending returns the number of wrapped items that are currently queued for
+	// fetching by the concurrent downloader.
+	pending() int
+
+	// capacity is responsible for calculating how many items of the abstracted
+	// type a particular peer is estimated to be able to retrieve within the
+	// alloted round trip time.
+	capacity(peer *peerConnection, rtt time.Duration) int
+
+	// updateCapacity is responsible for updating how many items of the abstracted
+	// type a particular peer is estimated to be able to retrieve in a unit time.
+	updateCapacity(peer *peerConnection, items int, elapsed time.Duration)
+
+	// reserve is responsible for allocating a requested number of pending items
+	// from the download queue to the specified peer.
+	reserve(peer *peerConnection, items int) (*fetchRequest, bool, bool)
+
+	// unreserve is resposible for removing the current retrieval allocation
+	// assigned to a specific peer and placing it back into the pool to allow
+	// reassigning to some other peer.
+	unreserve(peer string) int
+
+	// request is responsible for converting a generic fetch request into a typed
+	// one and sending it to the remote peer for fulfillment.
+	request(peer *peerConnection, req *fetchRequest, resCh chan *eth.Response) (*eth.Request, error)
+
+	// deliver is responsible for taking a generic response packet from the
+	// concurrent fetcher, unpacking the type specific data and delivering
+	// it to the downloader's queue.
+	deliver(peer *peerConnection, packet *eth.Response) (int, error)
+}
+
+// concurrentFetch iteratively downloads scheduled block parts, taking available
+// peers, reserving a chunk of fetch requests for each and waiting for delivery
+// or timeouts.
+func (d *Downloader) concurrentFetch(queue typedQueue) error {
+	// Create a delivery channel to accept responses from all peers
+	responses := make(chan *eth.Response)
+
+	// Track the currently active requests and their timeout order
+	pending := make(map[string]*eth.Request)
+	defer func() {
+		// Abort all requests on sync cycle cancellation. The requests may still
+		// be fulfilled by the remote side, but the dispatcher will not wait to
+		// deliver them since nobody's going to be listening.
+		for _, req := range pending {
+			req.Close()
+		}
+	}()
+	ordering := make(map[*eth.Request]int)
+	timeouts := prque.New(func(data interface{}, index int) {
+		ordering[data.(*eth.Request)] = index
+	})
+
+	timeout := time.NewTimer(0)
+	if !timeout.Stop() {
+		<-timeout.C
+	}
+	defer timeout.Stop()
+
+	// Track the timed-out but not-yet-answered requests separately. We want to
+	// keep tracking which peers are busy (potentially overloaded), so removing
+	// all trace of a timed out request is not good. We also can't just cancel
+	// the pending request altogether as that would prevent a late response from
+	// being delivered, thus never unblocking the peer.
+	stales := make(map[string]*eth.Request)
+	defer func() {
+		// Abort all requests on sync cycle cancellation. The requests may still
+		// be fulfilled by the remote side, but the dispatcher will not wait to
+		// deliver them since nobody's going to be listening.
+		for _, req := range stales {
+			req.Close()
+		}
+	}()
+	// Subscribe to peer lifecycle events to schedule tasks to new joiners and
+	// reschedule tasks upon disconnections. We don't care which event happened
+	// for simplicity, so just use a single channel.
+	peering := make(chan *peeringEvent, 64) // arbitrary buffer, just some burst protection
+
+	peeringSub := d.peers.SubscribeEvents(peering)
+	defer peeringSub.Unsubscribe()
+
+	// Prepare the queue and fetch block parts until the block header fetcher's done
+	finished := false
+	for {
+		// Short circuit if we lost all our peers
+		if d.peers.Len() == 0 {
+			return errNoPeers
+		}
+		// If there's nothing more to fetch, wait or terminate
+		if queue.pending() == 0 {
+			if len(pending) == 0 && finished {
+				return nil
+			}
+		} else {
+			// Send a download request to all idle peers, until throttled
+			var (
+				idles []*peerConnection
+				caps  []int
+			)
+			for _, peer := range d.peers.AllPeers() {
+				pending, stale := pending[peer.id], stales[peer.id]
+				if pending == nil && stale == nil {
+					idles = append(idles, peer)
+					caps = append(caps, queue.capacity(peer, time.Second))
+				} else if stale != nil {
+					if waited := time.Since(stale.Sent); waited > timeoutGracePeriod {
+						// Request has been in flight longer than the grace period
+						// permitted it, consider the peer malicious attempting to
+						// stall the sync.
+						peer.log.Warn("Peer stalling, dropping", "waited", common.PrettyDuration(waited))
+						d.dropPeer(peer.id)
+					}
+				}
+			}
+			sort.Sort(&peerCapacitySort{idles, caps})
+
+			var (
+				progressed bool
+				throttled  bool
+				queued     = queue.pending()
+			)
+			for _, peer := range idles {
+				// Short circuit if throttling activated or there are no more
+				// queued tasks to be retrieved
+				if throttled {
+					break
+				}
+				if queued = queue.pending(); queued == 0 {
+					break
+				}
+				// Reserve a chunk of fetches for a peer. A nil can mean either that
+				// no more headers are available, or that the peer is known not to
+				// have them.
+				request, progress, throttle := queue.reserve(peer, queue.capacity(peer, d.peers.rates.TargetRoundTrip()))
+				if progress {
+					progressed = true
+				}
+				if throttle {
+					throttled = true
+					throttleCounter.Inc(1)
+				}
+				if request == nil {
+					continue
+				}
+				// Fetch the chunk and make sure any errors return the hashes to the queue
+				req, err := queue.request(peer, request, responses)
+				if err != nil {
+					// Sending the request failed, which generally means the peer
+					// was diconnected in between assignment and network send.
+					// Although all peer removal operations return allocated tasks
+					// to the queue, that is async, and we can do better here by
+					// immediately pushing the unfulfilled requests.
+					queue.unreserve(peer.id) // TODO(karalabe): This needs a non-expiration method
+					continue
+				}
+				pending[peer.id] = req
+
+				ttl := d.peers.rates.TargetTimeout()
+				ordering[req] = timeouts.Size()
+
+				timeouts.Push(req, -time.Now().Add(ttl).UnixNano())
+				if timeouts.Size() == 1 {
+					timeout.Reset(ttl)
+				}
+			}
+			// Make sure that we have peers available for fetching. If all peers have been tried
+			// and all failed throw an error
+			if !progressed && !throttled && len(pending) == 0 && len(idles) == d.peers.Len() && queued > 0 {
+				return errPeersUnavailable
+			}
+		}
+		// Wait for something to happen
+		select {
+		case <-d.cancelCh:
+			// If sync was cancelled, tear down the parallel retriever. Pending
+			// requests will be cancelled locally, and the remote responses will
+			// be dropped when they arrive
+			return errCanceled
+
+		case event := <-peering:
+			// A peer joined or left, the tasks queue and allocations need to be
+			// checked for potential assignment or reassignment
+			peerid := event.peer.id
+
+			if event.join {
+				// Sanity check the internal state; this can be dropped later
+				if _, ok := pending[peerid]; ok {
+					event.peer.log.Error("Pending request exists for joining peer")
+				}
+				if _, ok := stales[peerid]; ok {
+					event.peer.log.Error("Stale request exists for joining peer")
+				}
+				// Loop back to the entry point for task assignment
+				continue
+			}
+			// A peer left, any existing requests need to be untracked, pending
+			// tasks returned and possible reassignment checked
+			if req, ok := pending[peerid]; ok {
+				queue.unreserve(peerid) // TODO(karalabe): This needs a non-expiration method
+				delete(pending, peerid)
+				req.Close()
+
+				if index, live := ordering[req]; live {
+					timeouts.Remove(index)
+					if index == 0 {
+						if !timeout.Stop() {
+							<-timeout.C
+						}
+						if timeouts.Size() > 0 {
+							_, exp := timeouts.Peek()
+							timeout.Reset(time.Until(time.Unix(0, -exp)))
+						}
+					}
+					delete(ordering, req)
+				}
+			}
+			if req, ok := stales[peerid]; ok {
+				delete(stales, peerid)
+				req.Close()
+			}
+
+		case <-timeout.C:
+			// Retrieve the next request which should have timed out. The check
+			// below is purely for to catch programming errors, given the correct
+			// code, there's no possible order of events that should result in a
+			// timeout firing for a non-existent event.
+			item, exp := timeouts.Peek()
+			if now, at := time.Now(), time.Unix(0, -exp); now.Before(at) {
+				log.Error("Timeout triggered but not reached", "left", at.Sub(now))
+				timeout.Reset(at.Sub(now))
+				continue
+			}
+			req := item.(*eth.Request)
+
+			// Stop tracking the timed out request from a timing perspective,
+			// cancel it, so it's not considered in-flight anymore, but keep
+			// the peer marked busy to prevent assigning a second request and
+			// overloading it further.
+			delete(pending, req.Peer)
+			stales[req.Peer] = req
+			delete(ordering, req)
+
+			timeouts.Pop()
+			if timeouts.Size() > 0 {
+				_, exp := timeouts.Peek()
+				timeout.Reset(time.Until(time.Unix(0, -exp)))
+			}
+			// New timeout potentially set if there are more requests pending,
+			// reschedule the failed one to a free peer
+			fails := queue.unreserve(req.Peer)
+
+			// Finally, update the peer's retrieval capacity, or if it's already
+			// below the minimum allowance, drop the peer. If a lot of retrieval
+			// elements expired, we might have overestimated the remote peer or
+			// perhaps ourselves. Only reset to minimal throughput but don't drop
+			// just yet.
+			//
+			// The reason the minimum threshold is 2 is that the downloader tries
+			// to estimate the bandwidth and latency of a peer separately, which
+			// requires pushing the measured capacity a bit and seeing how response
+			// times reacts, to it always requests one more than the minimum (i.e.
+			// min 2).
+			peer := d.peers.Peer(req.Peer)
+			if peer == nil {
+				// If the peer got disconnected in between, we should really have
+				// short-circuited it already. Just in case there's some strange
+				// codepath, leave this check in not to crash.
+				log.Error("Delivery timeout from unknown peer", "peer", req.Peer)
+				continue
+			}
+			if fails > 2 {
+				queue.updateCapacity(peer, 0, 0)
+			} else {
+				d.dropPeer(peer.id)
+
+				// If this peer was the master peer, abort sync immediately
+				d.cancelLock.RLock()
+				master := peer.id == d.cancelPeer
+				d.cancelLock.RUnlock()
+
+				if master {
+					d.cancel()
+					return errTimeout
+				}
+			}
+
+		case res := <-responses:
+			// Response arrived, it may be for an existing or an already timed
+			// out request. If the former, update the timeout heap and perhaps
+			// reschedule the timeout timer.
+			index, live := ordering[res.Req]
+			if live {
+				timeouts.Remove(index)
+				if index == 0 {
+					if !timeout.Stop() {
+						<-timeout.C
+					}
+					if timeouts.Size() > 0 {
+						_, exp := timeouts.Peek()
+						timeout.Reset(time.Until(time.Unix(0, -exp)))
+					}
+				}
+				delete(ordering, res.Req)
+			}
+			// Delete the pending request (if it still exists) and mark the peer idle
+			delete(pending, res.Req.Peer)
+			delete(stales, res.Req.Peer)
+
+			// Signal the dispatcher that the round trip is done. We'll drop the
+			// peer if the data turns out to be junk.
+			res.Done <- nil
+			res.Req.Close()
+
+			// If the peer was previously banned and failed to deliver its pack
+			// in a reasonable time frame, ignore its message.
+			if peer := d.peers.Peer(res.Req.Peer); peer != nil {
+				// Deliver the received chunk of data and check chain validity
+				accepted, err := queue.deliver(peer, res)
+				if errors.Is(err, errInvalidChain) {
+					return err
+				}
+				// Unless a peer delivered something completely else than requested (usually
+				// caused by a timed out request which came through in the end), set it to
+				// idle. If the delivery's stale, the peer should have already been idled.
+				if !errors.Is(err, errStaleDelivery) {
+					queue.updateCapacity(peer, accepted, res.Time)
+				}
+			}
+
+		case cont := <-queue.waker():
+			// The header fetcher sent a continuation flag, check if it's done
+			if !cont {
+				finished = true
+			}
+		}
+	}
+}

eth/downloader/fetchers_concurrent_bodies.go

@@ -0,0 +1,104 @@
+// Copyright 2021 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package downloader
+
+import (
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/eth/protocols/eth"
+	"github.com/ethereum/go-ethereum/log"
+)
+
+// bodyQueue implements typedQueue and is a type adapter between the generic
+// concurrent fetcher and the downloader.
+type bodyQueue Downloader
+
+// waker returns a notification channel that gets pinged in case more body
+// fetches have been queued up, so the fetcher might assign it to idle peers.
+func (q *bodyQueue) waker() chan bool {
+	return q.queue.blockWakeCh
+}
+
+// pending returns the number of bodies that are currently queued for fetching
+// by the concurrent downloader.
+func (q *bodyQueue) pending() int {
+	return q.queue.PendingBodies()
+}
+
+// capacity is responsible for calculating how many bodies a particular peer is
+// estimated to be able to retrieve within the alloted round trip time.
+func (q *bodyQueue) capacity(peer *peerConnection, rtt time.Duration) int {
+	return peer.BodyCapacity(rtt)
+}
+
+// updateCapacity is responsible for updating how many bodies a particular peer
+// is estimated to be able to retrieve in a unit time.
+func (q *bodyQueue) updateCapacity(peer *peerConnection, items int, span time.Duration) {
+	peer.UpdateBodyRate(items, span)
+}
+
+// reserve is responsible for allocating a requested number of pending bodies
+// from the download queue to the specified peer.
+func (q *bodyQueue) reserve(peer *peerConnection, items int) (*fetchRequest, bool, bool) {
+	return q.queue.ReserveBodies(peer, items)
+}
+
+// unreserve is resposible for removing the current body retrieval allocation
+// assigned to a specific peer and placing it back into the pool to allow
+// reassigning to some other peer.
+func (q *bodyQueue) unreserve(peer string) int {
+	fails := q.queue.ExpireBodies(peer)
+	if fails > 2 {
+		log.Trace("Body delivery timed out", "peer", peer)
+	} else {
+		log.Debug("Body delivery stalling", "peer", peer)
+	}
+	return fails
+}
+
+// request is responsible for converting a generic fetch request into a body
+// one and sending it to the remote peer for fulfillment.
+func (q *bodyQueue) request(peer *peerConnection, req *fetchRequest, resCh chan *eth.Response) (*eth.Request, error) {
+	peer.log.Trace("Requesting new batch of bodies", "count", len(req.Headers), "from", req.Headers[0].Number)
+	if q.bodyFetchHook != nil {
+		q.bodyFetchHook(req.Headers)
+	}
+
+	hashes := make([]common.Hash, 0, len(req.Headers))
+	for _, header := range req.Headers {
+		hashes = append(hashes, header.Hash())
+	}
+	return peer.peer.RequestBodies(hashes, resCh)
+}
+
+// deliver is responsible for taking a generic response packet from the concurrent
+// fetcher, unpacking the body data and delivering it to the downloader's queue.
+func (q *bodyQueue) deliver(peer *peerConnection, packet *eth.Response) (int, error) {
+	txs, uncles := packet.Res.(*eth.BlockBodiesPacket).Unpack()
+
+	accepted, err := q.queue.DeliverBodies(peer.id, txs, uncles)
+	switch {
+	case err == nil && len(txs) == 0:
+		peer.log.Trace("Requested bodies delivered")
+	case err == nil:
+		peer.log.Trace("Delivered new batch of bodies", "count", len(txs), "accepted", accepted)
+	default:
+		peer.log.Debug("Failed to deliver retrieved bodies", "err", err)
+	}
+	return accepted, err
+}

eth/downloader/fetchers_concurrent_headers.go

@@ -0,0 +1,95 @@
+// Copyright 2021 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package downloader
+
+import (
+	"time"
+
+	"github.com/ethereum/go-ethereum/eth/protocols/eth"
+	"github.com/ethereum/go-ethereum/log"
+)
+
+// headerQueue implements typedQueue and is a type adapter between the generic
+// concurrent fetcher and the downloader.
+type headerQueue Downloader
+
+// waker returns a notification channel that gets pinged in case more header
+// fetches have been queued up, so the fetcher might assign it to idle peers.
+func (q *headerQueue) waker() chan bool {
+	return q.queue.headerContCh
+}
+
+// pending returns the number of headers that are currently queued for fetching
+// by the concurrent downloader.
+func (q *headerQueue) pending() int {
+	return q.queue.PendingHeaders()
+}
+
+// capacity is responsible for calculating how many headers a particular peer is
+// estimated to be able to retrieve within the alloted round trip time.
+func (q *headerQueue) capacity(peer *peerConnection, rtt time.Duration) int {
+	return peer.HeaderCapacity(rtt)
+}
+
+// updateCapacity is responsible for updating how many headers a particular peer
+// is estimated to be able to retrieve in a unit time.
+func (q *headerQueue) updateCapacity(peer *peerConnection, items int, span time.Duration) {
+	peer.UpdateHeaderRate(items, span)
+}
+
+// reserve is responsible for allocating a requested number of pending headers
+// from the download queue to the specified peer.
+func (q *headerQueue) reserve(peer *peerConnection, items int) (*fetchRequest, bool, bool) {
+	return q.queue.ReserveHeaders(peer, items), false, false
+}
+
+// unreserve is resposible for removing the current header retrieval allocation
+// assigned to a specific peer and placing it back into the pool to allow
+// reassigning to some other peer.
+func (q *headerQueue) unreserve(peer string) int {
+	fails := q.queue.ExpireHeaders(peer)
+	if fails > 2 {
+		log.Trace("Header delivery timed out", "peer", peer)
+	} else {
+		log.Debug("Header delivery stalling", "peer", peer)
+	}
+	return fails
+}
+
+// request is responsible for converting a generic fetch request into a header
+// one and sending it to the remote peer for fulfillment.
+func (q *headerQueue) request(peer *peerConnection, req *fetchRequest, resCh chan *eth.Response) (*eth.Request, error) {
+	peer.log.Trace("Requesting new batch of headers", "from", req.From)
+	return peer.peer.RequestHeadersByNumber(req.From, MaxHeaderFetch, 0, false, resCh)
+}
+
+// deliver is responsible for taking a generic response packet from the concurrent
+// fetcher, unpacking the header data and delivering it to the downloader's queue.
+func (q *headerQueue) deliver(peer *peerConnection, packet *eth.Response) (int, error) {
+	headers := *packet.Res.(*eth.BlockHeadersPacket)
+
+	accepted, err := q.queue.DeliverHeaders(peer.id, headers, q.headerProcCh)
+	switch {
+	case err == nil && len(headers) == 0:
+		peer.log.Trace("Requested headers delivered")
+	case err == nil:
+		peer.log.Trace("Delivered new batch of headers", "count", len(headers), "accepted", accepted)
+	default:
+		peer.log.Debug("Failed to deliver retrieved headers", "err", err)
+	}
+	return accepted, err
+}

eth/downloader/fetchers_concurrent_receipts.go

@@ -0,0 +1,103 @@
+// Copyright 2021 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package downloader
+
+import (
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/eth/protocols/eth"
+	"github.com/ethereum/go-ethereum/log"
+)
+
+// receiptQueue implements typedQueue and is a type adapter between the generic
+// concurrent fetcher and the downloader.
+type receiptQueue Downloader
+
+// waker returns a notification channel that gets pinged in case more reecipt
+// fetches have been queued up, so the fetcher might assign it to idle peers.
+func (q *receiptQueue) waker() chan bool {
+	return q.queue.receiptWakeCh
+}
+
+// pending returns the number of receipt that are currently queued for fetching
+// by the concurrent downloader.
+func (q *receiptQueue) pending() int {
+	return q.queue.PendingReceipts()
+}
+
+// capacity is responsible for calculating how many receipts a particular peer is
+// estimated to be able to retrieve within the alloted round trip time.
+func (q *receiptQueue) capacity(peer *peerConnection, rtt time.Duration) int {
+	return peer.ReceiptCapacity(rtt)
+}
+
+// updateCapacity is responsible for updating how many receipts a particular peer
+// is estimated to be able to retrieve in a unit time.
+func (q *receiptQueue) updateCapacity(peer *peerConnection, items int, span time.Duration) {
+	peer.UpdateReceiptRate(items, span)
+}
+
+// reserve is responsible for allocating a requested number of pending receipts
+// from the download queue to the specified peer.
+func (q *receiptQueue) reserve(peer *peerConnection, items int) (*fetchRequest, bool, bool) {
+	return q.queue.ReserveReceipts(peer, items)
+}
+
+// unreserve is resposible for removing the current receipt retrieval allocation
+// assigned to a specific peer and placing it back into the pool to allow
+// reassigning to some other peer.
+func (q *receiptQueue) unreserve(peer string) int {
+	fails := q.queue.ExpireReceipts(peer)
+	if fails > 2 {
+		log.Trace("Receipt delivery timed out", "peer", peer)
+	} else {
+		log.Debug("Receipt delivery stalling", "peer", peer)
+	}
+	return fails
+}
+
+// request is responsible for converting a generic fetch request into a receipt
+// one and sending it to the remote peer for fulfillment.
+func (q *receiptQueue) request(peer *peerConnection, req *fetchRequest, resCh chan *eth.Response) (*eth.Request, error) {
+	peer.log.Trace("Requesting new batch of receipts", "count", len(req.Headers), "from", req.Headers[0].Number)
+	if q.receiptFetchHook != nil {
+		q.receiptFetchHook(req.Headers)
+	}
+	hashes := make([]common.Hash, 0, len(req.Headers))
+	for _, header := range req.Headers {
+		hashes = append(hashes, header.Hash())
+	}
+	return peer.peer.RequestReceipts(hashes, resCh)
+}
+
+// deliver is responsible for taking a generic response packet from the concurrent
+// fetcher, unpacking the receipt data and delivering it to the downloader's queue.
+func (q *receiptQueue) deliver(peer *peerConnection, packet *eth.Response) (int, error) {
+	receipts := *packet.Res.(*eth.ReceiptsPacket)
+
+	accepted, err := q.queue.DeliverReceipts(peer.id, receipts)
+	switch {
+	case err == nil && len(receipts) == 0:
+		peer.log.Trace("Requested receipts delivered")
+	case err == nil:
+		peer.log.Trace("Delivered new batch of receipts", "count", len(receipts), "accepted", accepted)
+	default:
+		peer.log.Debug("Failed to deliver retrieved receipts", "err", err)
+	}
+	return accepted, err
+}

eth/downloader/metrics.go

@@ -38,8 +38,5 @@ var (
 	receiptDropMeter    = metrics.NewRegisteredMeter("eth/downloader/receipts/drop", nil)
 	receiptTimeoutMeter = metrics.NewRegisteredMeter("eth/downloader/receipts/timeout", nil)
 
-	stateInMeter   = metrics.NewRegisteredMeter("eth/downloader/states/in", nil)
-	stateDropMeter = metrics.NewRegisteredMeter("eth/downloader/states/drop", nil)
-
 	throttleCounter = metrics.NewRegisteredCounter("eth/downloader/throttle", nil)
 )

eth/downloader/modes.go

@@ -24,7 +24,6 @@ type SyncMode uint32
 
 const (
 	FullSync  SyncMode = iota // Synchronise the entire blockchain history from full blocks
-	FastSync                  // Quickly download the headers, full sync only at the chain
 	SnapSync                  // Download the chain and the state via compact snapshots
 	LightSync                 // Download only the headers and terminate afterwards
 )
@@ -38,8 +37,6 @@ func (mode SyncMode) String() string {
 	switch mode {
 	case FullSync:
 		return "full"
-	case FastSync:
-		return "fast"
 	case SnapSync:
 		return "snap"
 	case LightSync:
@@ -53,8 +50,6 @@ func (mode SyncMode) MarshalText() ([]byte, error) {
 	switch mode {
 	case FullSync:
 		return []byte("full"), nil
-	case FastSync:
-		return []byte("fast"), nil
 	case SnapSync:
 		return []byte("snap"), nil
 	case LightSync:
@@ -68,14 +63,12 @@ func (mode *SyncMode) UnmarshalText(text []byte) error {
 	switch string(text) {
 	case "full":
 		*mode = FullSync
-	case "fast":
-		*mode = FastSync
 	case "snap":
 		*mode = SnapSync
 	case "light":
 		*mode = LightSync
 	default:
-		return fmt.Errorf(`unknown sync mode %q, want "full", "fast" or "light"`, text)
+		return fmt.Errorf(`unknown sync mode %q, want "full", "snap" or "light"`, text)
 	}
 	return nil
 }

eth/downloader/peer.go

@@ -22,9 +22,7 @@ package downloader
 import (
 	"errors"
 	"math/big"
-	"sort"
 	"sync"
-	"sync/atomic"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -39,7 +37,6 @@ const (
 )
 
 var (
-	errAlreadyFetching   = errors.New("already fetching blocks from peer")
 	errAlreadyRegistered = errors.New("peer is already registered")
 	errNotRegistered     = errors.New("peer is not registered")
 )
@@ -48,16 +45,6 @@ var (
 type peerConnection struct {
 	id string // Unique identifier of the peer
 
-	headerIdle  int32 // Current header activity state of the peer (idle = 0, active = 1)
-	blockIdle   int32 // Current block activity state of the peer (idle = 0, active = 1)
-	receiptIdle int32 // Current receipt activity state of the peer (idle = 0, active = 1)
-	stateIdle   int32 // Current node data activity state of the peer (idle = 0, active = 1)
-
-	headerStarted  time.Time // Time instance when the last header fetch was started
-	blockStarted   time.Time // Time instance when the last block (body) fetch was started
-	receiptStarted time.Time // Time instance when the last receipt fetch was started
-	stateStarted   time.Time // Time instance when the last node data fetch was started
-
 	rates   *msgrate.Tracker         // Tracker to hone in on the number of items retrievable per second
 	lacking map[common.Hash]struct{} // Set of hashes not to request (didn't have previously)
 
@@ -71,16 +58,15 @@ type peerConnection struct {
 // LightPeer encapsulates the methods required to synchronise with a remote light peer.
 type LightPeer interface {
 	Head() (common.Hash, *big.Int)
-	RequestHeadersByHash(common.Hash, int, int, bool) error
+	RequestHeadersByHash(common.Hash, int, int, bool, chan *eth.Response) (*eth.Request, error)
-	RequestHeadersByNumber(uint64, int, int, bool) error
+	RequestHeadersByNumber(uint64, int, int, bool, chan *eth.Response) (*eth.Request, error)
 }
 
 // Peer encapsulates the methods required to synchronise with a remote full peer.
 type Peer interface {
 	LightPeer
-	RequestBodies([]common.Hash) error
+	RequestBodies([]common.Hash, chan *eth.Response) (*eth.Request, error)
-	RequestReceipts([]common.Hash) error
+	RequestReceipts([]common.Hash, chan *eth.Response) (*eth.Request, error)
-	RequestNodeData([]common.Hash) error
 }
 
 // lightPeerWrapper wraps a LightPeer struct, stubbing out the Peer-only methods.
@@ -89,21 +75,18 @@ type lightPeerWrapper struct {
 }
 
 func (w *lightPeerWrapper) Head() (common.Hash, *big.Int) { return w.peer.Head() }
-func (w *lightPeerWrapper) RequestHeadersByHash(h common.Hash, amount int, skip int, reverse bool) error {
+func (w *lightPeerWrapper) RequestHeadersByHash(h common.Hash, amount int, skip int, reverse bool, sink chan *eth.Response) (*eth.Request, error) {
-	return w.peer.RequestHeadersByHash(h, amount, skip, reverse)
+	return w.peer.RequestHeadersByHash(h, amount, skip, reverse, sink)
 }
-func (w *lightPeerWrapper) RequestHeadersByNumber(i uint64, amount int, skip int, reverse bool) error {
+func (w *lightPeerWrapper) RequestHeadersByNumber(i uint64, amount int, skip int, reverse bool, sink chan *eth.Response) (*eth.Request, error) {
-	return w.peer.RequestHeadersByNumber(i, amount, skip, reverse)
+	return w.peer.RequestHeadersByNumber(i, amount, skip, reverse, sink)
 }
-func (w *lightPeerWrapper) RequestBodies([]common.Hash) error {
+func (w *lightPeerWrapper) RequestBodies([]common.Hash, chan *eth.Response) (*eth.Request, error) {
 	panic("RequestBodies not supported in light client mode sync")
 }
-func (w *lightPeerWrapper) RequestReceipts([]common.Hash) error {
+func (w *lightPeerWrapper) RequestReceipts([]common.Hash, chan *eth.Response) (*eth.Request, error) {
 	panic("RequestReceipts not supported in light client mode sync")
 }
-func (w *lightPeerWrapper) RequestNodeData([]common.Hash) error {
-	panic("RequestNodeData not supported in light client mode sync")
-}
 
 // newPeerConnection creates a new downloader peer.
 func newPeerConnection(id string, version uint, peer Peer, logger log.Logger) *peerConnection {
@@ -121,114 +104,28 @@ func (p *peerConnection) Reset() {
 	p.lock.Lock()
 	defer p.lock.Unlock()
 
-	atomic.StoreInt32(&p.headerIdle, 0)
-	atomic.StoreInt32(&p.blockIdle, 0)
-	atomic.StoreInt32(&p.receiptIdle, 0)
-	atomic.StoreInt32(&p.stateIdle, 0)
-
 	p.lacking = make(map[common.Hash]struct{})
 }
 
-// FetchHeaders sends a header retrieval request to the remote peer.
+// UpdateHeaderRate updates the peer's estimated header retrieval throughput with
-func (p *peerConnection) FetchHeaders(from uint64, count int) error {
+// the current measurement.
-	// Short circuit if the peer is already fetching
+func (p *peerConnection) UpdateHeaderRate(delivered int, elapsed time.Duration) {
-	if !atomic.CompareAndSwapInt32(&p.headerIdle, 0, 1) {
+	p.rates.Update(eth.BlockHeadersMsg, elapsed, delivered)
-		return errAlreadyFetching
-	}
-	p.headerStarted = time.Now()
-
-	// Issue the header retrieval request (absolute upwards without gaps)
-	go p.peer.RequestHeadersByNumber(from, count, 0, false)
-
-	return nil
 }
 
-// FetchBodies sends a block body retrieval request to the remote peer.
+// UpdateBodyRate updates the peer's estimated body retrieval throughput with the
-func (p *peerConnection) FetchBodies(request *fetchRequest) error {
+// current measurement.
-	// Short circuit if the peer is already fetching
+func (p *peerConnection) UpdateBodyRate(delivered int, elapsed time.Duration) {
-	if !atomic.CompareAndSwapInt32(&p.blockIdle, 0, 1) {
+	p.rates.Update(eth.BlockBodiesMsg, elapsed, delivered)
-		return errAlreadyFetching
-	}
-	p.blockStarted = time.Now()
-
-	go func() {
-		// Convert the header set to a retrievable slice
-		hashes := make([]common.Hash, 0, len(request.Headers))
-		for _, header := range request.Headers {
-			hashes = append(hashes, header.Hash())
-		}
-		p.peer.RequestBodies(hashes)
-	}()
-
-	return nil
 }
 
-// FetchReceipts sends a receipt retrieval request to the remote peer.
+// UpdateReceiptRate updates the peer's estimated receipt retrieval throughput
-func (p *peerConnection) FetchReceipts(request *fetchRequest) error {
+// with the current measurement.
-	// Short circuit if the peer is already fetching
+func (p *peerConnection) UpdateReceiptRate(delivered int, elapsed time.Duration) {
-	if !atomic.CompareAndSwapInt32(&p.receiptIdle, 0, 1) {
+	p.rates.Update(eth.ReceiptsMsg, elapsed, delivered)
-		return errAlreadyFetching
-	}
-	p.receiptStarted = time.Now()
-
-	go func() {
-		// Convert the header set to a retrievable slice
-		hashes := make([]common.Hash, 0, len(request.Headers))
-		for _, header := range request.Headers {
-			hashes = append(hashes, header.Hash())
-		}
-		p.peer.RequestReceipts(hashes)
-	}()
-
-	return nil
 }
 
-// FetchNodeData sends a node state data retrieval request to the remote peer.
+// HeaderCapacity retrieves the peer's header download allowance based on its
-func (p *peerConnection) FetchNodeData(hashes []common.Hash) error {
-	// Short circuit if the peer is already fetching
-	if !atomic.CompareAndSwapInt32(&p.stateIdle, 0, 1) {
-		return errAlreadyFetching
-	}
-	p.stateStarted = time.Now()
-
-	go p.peer.RequestNodeData(hashes)
-
-	return nil
-}
-
-// SetHeadersIdle sets the peer to idle, allowing it to execute new header retrieval
-// requests. Its estimated header retrieval throughput is updated with that measured
-// just now.
-func (p *peerConnection) SetHeadersIdle(delivered int, deliveryTime time.Time) {
-	p.rates.Update(eth.BlockHeadersMsg, deliveryTime.Sub(p.headerStarted), delivered)
-	atomic.StoreInt32(&p.headerIdle, 0)
-}
-
-// SetBodiesIdle sets the peer to idle, allowing it to execute block body retrieval
-// requests. Its estimated body retrieval throughput is updated with that measured
-// just now.
-func (p *peerConnection) SetBodiesIdle(delivered int, deliveryTime time.Time) {
-	p.rates.Update(eth.BlockBodiesMsg, deliveryTime.Sub(p.blockStarted), delivered)
-	atomic.StoreInt32(&p.blockIdle, 0)
-}
-
-// SetReceiptsIdle sets the peer to idle, allowing it to execute new receipt
-// retrieval requests. Its estimated receipt retrieval throughput is updated
-// with that measured just now.
-func (p *peerConnection) SetReceiptsIdle(delivered int, deliveryTime time.Time) {
-	p.rates.Update(eth.ReceiptsMsg, deliveryTime.Sub(p.receiptStarted), delivered)
-	atomic.StoreInt32(&p.receiptIdle, 0)
-}
-
-// SetNodeDataIdle sets the peer to idle, allowing it to execute new state trie
-// data retrieval requests. Its estimated state retrieval throughput is updated
-// with that measured just now.
-func (p *peerConnection) SetNodeDataIdle(delivered int, deliveryTime time.Time) {
-	p.rates.Update(eth.NodeDataMsg, deliveryTime.Sub(p.stateStarted), delivered)
-	atomic.StoreInt32(&p.stateIdle, 0)
-}
-
-// HeaderCapacity retrieves the peers header download allowance based on its
 // previously discovered throughput.
 func (p *peerConnection) HeaderCapacity(targetRTT time.Duration) int {
 	cap := p.rates.Capacity(eth.BlockHeadersMsg, targetRTT)
@@ -238,9 +135,9 @@ func (p *peerConnection) HeaderCapacity(targetRTT time.Duration) int {
 	return cap
 }
 
-// BlockCapacity retrieves the peers block download allowance based on its
+// BodyCapacity retrieves the peer's body download allowance based on its
 // previously discovered throughput.
-func (p *peerConnection) BlockCapacity(targetRTT time.Duration) int {
+func (p *peerConnection) BodyCapacity(targetRTT time.Duration) int {
 	cap := p.rates.Capacity(eth.BlockBodiesMsg, targetRTT)
 	if cap > MaxBlockFetch {
 		cap = MaxBlockFetch
@@ -258,16 +155,6 @@ func (p *peerConnection) ReceiptCapacity(targetRTT time.Duration) int {
 	return cap
 }
 
-// NodeDataCapacity retrieves the peers state download allowance based on its
-// previously discovered throughput.
-func (p *peerConnection) NodeDataCapacity(targetRTT time.Duration) int {
-	cap := p.rates.Capacity(eth.NodeDataMsg, targetRTT)
-	if cap > MaxStateFetch {
-		cap = MaxStateFetch
-	}
-	return cap
-}
-
 // MarkLacking appends a new entity to the set of items (blocks, receipts, states)
 // that a peer is known not to have (i.e. have been requested before). If the
 // set reaches its maximum allowed capacity, items are randomly dropped off.
@@ -294,14 +181,19 @@ func (p *peerConnection) Lacks(hash common.Hash) bool {
 	return ok
 }
 
+// peeringEvent is sent on the peer event feed when a remote peer connects or
+// disconnects.
+type peeringEvent struct {
+	peer *peerConnection
+	join bool
+}
+
 // peerSet represents the collection of active peer participating in the chain
 // download procedure.
 type peerSet struct {
 	peers  map[string]*peerConnection
 	rates  *msgrate.Trackers // Set of rate trackers to give the sync a common beat
-
+	events event.Feed        // Feed to publish peer lifecycle events on
-	newPeerFeed  event.Feed
-	peerDropFeed event.Feed
 
 	lock sync.RWMutex
 }
@@ -314,14 +206,9 @@ func newPeerSet() *peerSet {
 	}
 }
 
-// SubscribeNewPeers subscribes to peer arrival events.
+// SubscribeEvents subscribes to peer arrival and departure events.
-func (ps *peerSet) SubscribeNewPeers(ch chan<- *peerConnection) event.Subscription {
+func (ps *peerSet) SubscribeEvents(ch chan<- *peeringEvent) event.Subscription {
-	return ps.newPeerFeed.Subscribe(ch)
+	return ps.events.Subscribe(ch)
-}
-
-// SubscribePeerDrops subscribes to peer departure events.
-func (ps *peerSet) SubscribePeerDrops(ch chan<- *peerConnection) event.Subscription {
-	return ps.peerDropFeed.Subscribe(ch)
 }
 
 // Reset iterates over the current peer set, and resets each of the known peers
@@ -355,7 +242,7 @@ func (ps *peerSet) Register(p *peerConnection) error {
 	ps.peers[p.id] = p
 	ps.lock.Unlock()
 
-	ps.newPeerFeed.Send(p)
+	ps.events.Send(&peeringEvent{peer: p, join: true})
 	return nil
 }
 
@@ -372,7 +259,7 @@ func (ps *peerSet) Unregister(id string) error {
 	ps.rates.Untrack(id)
 	ps.lock.Unlock()
 
-	ps.peerDropFeed.Send(p)
+	ps.events.Send(&peeringEvent{peer: p, join: false})
 	return nil
 }
 
@@ -404,82 +291,6 @@ func (ps *peerSet) AllPeers() []*peerConnection {
 	return list
 }
 
-// HeaderIdlePeers retrieves a flat list of all the currently header-idle peers
-// within the active peer set, ordered by their reputation.
-func (ps *peerSet) HeaderIdlePeers() ([]*peerConnection, int) {
-	idle := func(p *peerConnection) bool {
-		return atomic.LoadInt32(&p.headerIdle) == 0
-	}
-	throughput := func(p *peerConnection) int {
-		return p.rates.Capacity(eth.BlockHeadersMsg, time.Second)
-	}
-	return ps.idlePeers(eth.ETH66, eth.ETH66, idle, throughput)
-}
-
-// BodyIdlePeers retrieves a flat list of all the currently body-idle peers within
-// the active peer set, ordered by their reputation.
-func (ps *peerSet) BodyIdlePeers() ([]*peerConnection, int) {
-	idle := func(p *peerConnection) bool {
-		return atomic.LoadInt32(&p.blockIdle) == 0
-	}
-	throughput := func(p *peerConnection) int {
-		return p.rates.Capacity(eth.BlockBodiesMsg, time.Second)
-	}
-	return ps.idlePeers(eth.ETH66, eth.ETH66, idle, throughput)
-}
-
-// ReceiptIdlePeers retrieves a flat list of all the currently receipt-idle peers
-// within the active peer set, ordered by their reputation.
-func (ps *peerSet) ReceiptIdlePeers() ([]*peerConnection, int) {
-	idle := func(p *peerConnection) bool {
-		return atomic.LoadInt32(&p.receiptIdle) == 0
-	}
-	throughput := func(p *peerConnection) int {
-		return p.rates.Capacity(eth.ReceiptsMsg, time.Second)
-	}
-	return ps.idlePeers(eth.ETH66, eth.ETH66, idle, throughput)
-}
-
-// NodeDataIdlePeers retrieves a flat list of all the currently node-data-idle
-// peers within the active peer set, ordered by their reputation.
-func (ps *peerSet) NodeDataIdlePeers() ([]*peerConnection, int) {
-	idle := func(p *peerConnection) bool {
-		return atomic.LoadInt32(&p.stateIdle) == 0
-	}
-	throughput := func(p *peerConnection) int {
-		return p.rates.Capacity(eth.NodeDataMsg, time.Second)
-	}
-	return ps.idlePeers(eth.ETH66, eth.ETH66, idle, throughput)
-}
-
-// idlePeers retrieves a flat list of all currently idle peers satisfying the
-// protocol version constraints, using the provided function to check idleness.
-// The resulting set of peers are sorted by their capacity.
-func (ps *peerSet) idlePeers(minProtocol, maxProtocol uint, idleCheck func(*peerConnection) bool, capacity func(*peerConnection) int) ([]*peerConnection, int) {
-	ps.lock.RLock()
-	defer ps.lock.RUnlock()
-
-	var (
-		total = 0
-		idle  = make([]*peerConnection, 0, len(ps.peers))
-		tps   = make([]int, 0, len(ps.peers))
-	)
-	for _, p := range ps.peers {
-		if p.version >= minProtocol && p.version <= maxProtocol {
-			if idleCheck(p) {
-				idle = append(idle, p)
-				tps = append(tps, capacity(p))
-			}
-			total++
-		}
-	}
-
-	// And sort them
-	sortPeers := &peerCapacitySort{idle, tps}
-	sort.Sort(sortPeers)
-	return sortPeers.p, total
-}
-
 // peerCapacitySort implements sort.Interface.
 // It sorts peer connections by capacity (descending).
 type peerCapacitySort struct {

eth/downloader/queue.go

@@ -54,8 +54,8 @@ var (
 // fetchRequest is a currently running data retrieval operation.
 type fetchRequest struct {
 	Peer    *peerConnection // Peer to which the request was sent
-	From    uint64          // [eth/62] Requested chain element index (used for skeleton fills only)
+	From    uint64          // Requested chain element index (used for skeleton fills only)
-	Headers []*types.Header // [eth/62] Requested headers, sorted by request order
+	Headers []*types.Header // Requested headers, sorted by request order
 	Time    time.Time       // Time when the request was made
 }
 
@@ -127,10 +127,12 @@ type queue struct {
 	blockTaskPool  map[common.Hash]*types.Header // Pending block (body) retrieval tasks, mapping hashes to headers
 	blockTaskQueue *prque.Prque                  // Priority queue of the headers to fetch the blocks (bodies) for
 	blockPendPool  map[string]*fetchRequest      // Currently pending block (body) retrieval operations
+	blockWakeCh    chan bool                     // Channel to notify the block fetcher of new tasks
 
 	receiptTaskPool  map[common.Hash]*types.Header // Pending receipt retrieval tasks, mapping hashes to headers
 	receiptTaskQueue *prque.Prque                  // Priority queue of the headers to fetch the receipts for
 	receiptPendPool  map[string]*fetchRequest      // Currently pending receipt retrieval operations
+	receiptWakeCh    chan bool                     // Channel to notify when receipt fetcher of new tasks
 
 	resultCache *resultStore       // Downloaded but not yet delivered fetch results
 	resultSize  common.StorageSize // Approximate size of a block (exponential moving average)
@@ -146,9 +148,11 @@ type queue struct {
 func newQueue(blockCacheLimit int, thresholdInitialSize int) *queue {
 	lock := new(sync.RWMutex)
 	q := &queue{
-		headerContCh:     make(chan bool),
+		headerContCh:     make(chan bool, 1),
 		blockTaskQueue:   prque.New(nil),
+		blockWakeCh:      make(chan bool, 1),
 		receiptTaskQueue: prque.New(nil),
+		receiptWakeCh:    make(chan bool, 1),
 		active:           sync.NewCond(lock),
 		lock:             lock,
 	}
@@ -196,8 +200,8 @@ func (q *queue) PendingHeaders() int {
 	return q.headerTaskQueue.Size()
 }
 
-// PendingBlocks retrieves the number of block (body) requests pending for retrieval.
+// PendingBodies retrieves the number of block body requests pending for retrieval.
-func (q *queue) PendingBlocks() int {
+func (q *queue) PendingBodies() int {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
@@ -212,15 +216,6 @@ func (q *queue) PendingReceipts() int {
 	return q.receiptTaskQueue.Size()
 }
 
-// InFlightHeaders retrieves whether there are header fetch requests currently
-// in flight.
-func (q *queue) InFlightHeaders() bool {
-	q.lock.Lock()
-	defer q.lock.Unlock()
-
-	return len(q.headerPendPool) > 0
-}
-
 // InFlightBlocks retrieves whether there are block fetch requests currently in
 // flight.
 func (q *queue) InFlightBlocks() bool {
@@ -318,7 +313,7 @@ func (q *queue) Schedule(headers []*types.Header, from uint64) []*types.Header {
 			q.blockTaskQueue.Push(header, -int64(header.Number.Uint64()))
 		}
 		// Queue for receipt retrieval
-		if q.mode == FastSync && !header.EmptyReceipts() {
+		if q.mode == SnapSync && !header.EmptyReceipts() {
 			if _, ok := q.receiptTaskPool[hash]; ok {
 				log.Warn("Header already scheduled for receipt fetch", "number", header.Number, "hash", hash)
 			} else {
@@ -383,6 +378,13 @@ func (q *queue) Results(block bool) []*fetchResult {
 	throttleThreshold := uint64((common.StorageSize(blockCacheMemory) + q.resultSize - 1) / q.resultSize)
 	throttleThreshold = q.resultCache.SetThrottleThreshold(throttleThreshold)
 
+	// With results removed from the cache, wake throttled fetchers
+	for _, ch := range []chan bool{q.blockWakeCh, q.receiptWakeCh} {
+		select {
+		case ch <- true:
+		default:
+		}
+	}
 	// Log some info at certain times
 	if time.Since(q.lastStatLog) > 60*time.Second {
 		q.lastStatLog = time.Now()
@@ -503,7 +505,7 @@ func (q *queue) reserveHeaders(p *peerConnection, count int, taskPool map[common
 		// we can ask the resultcache if this header is within the
 		// "prioritized" segment of blocks. If it is not, we need to throttle
 
-		stale, throttle, item, err := q.resultCache.AddFetch(header, q.mode == FastSync)
+		stale, throttle, item, err := q.resultCache.AddFetch(header, q.mode == SnapSync)
 		if stale {
 			// Don't put back in the task queue, this item has already been
 			// delivered upstream
@@ -566,40 +568,6 @@ func (q *queue) reserveHeaders(p *peerConnection, count int, taskPool map[common
 	return request, progress, throttled
 }
 
-// CancelHeaders aborts a fetch request, returning all pending skeleton indexes to the queue.
-func (q *queue) CancelHeaders(request *fetchRequest) {
-	q.lock.Lock()
-	defer q.lock.Unlock()
-	q.cancel(request, q.headerTaskQueue, q.headerPendPool)
-}
-
-// CancelBodies aborts a body fetch request, returning all pending headers to the
-// task queue.
-func (q *queue) CancelBodies(request *fetchRequest) {
-	q.lock.Lock()
-	defer q.lock.Unlock()
-	q.cancel(request, q.blockTaskQueue, q.blockPendPool)
-}
-
-// CancelReceipts aborts a body fetch request, returning all pending headers to
-// the task queue.
-func (q *queue) CancelReceipts(request *fetchRequest) {
-	q.lock.Lock()
-	defer q.lock.Unlock()
-	q.cancel(request, q.receiptTaskQueue, q.receiptPendPool)
-}
-
-// Cancel aborts a fetch request, returning all pending hashes to the task queue.
-func (q *queue) cancel(request *fetchRequest, taskQueue *prque.Prque, pendPool map[string]*fetchRequest) {
-	if request.From > 0 {
-		taskQueue.Push(request.From, -int64(request.From))
-	}
-	for _, header := range request.Headers {
-		taskQueue.Push(header, -int64(header.Number.Uint64()))
-	}
-	delete(pendPool, request.Peer.id)
-}
-
 // Revoke cancels all pending requests belonging to a given peer. This method is
 // meant to be called during a peer drop to quickly reassign owned data fetches
 // to remaining nodes.
@@ -607,6 +575,10 @@ func (q *queue) Revoke(peerID string) {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
+	if request, ok := q.headerPendPool[peerID]; ok {
+		q.headerTaskQueue.Push(request.From, -int64(request.From))
+		delete(q.headerPendPool, peerID)
+	}
 	if request, ok := q.blockPendPool[peerID]; ok {
 		for _, header := range request.Headers {
 			q.blockTaskQueue.Push(header, -int64(header.Number.Uint64()))
@@ -621,62 +593,60 @@ func (q *queue) Revoke(peerID string) {
 	}
 }
 
-// ExpireHeaders checks for in flight requests that exceeded a timeout allowance,
+// ExpireHeaders cancels a request that timed out and moves the pending fetch
-// canceling them and returning the responsible peers for penalisation.
+// task back into the queue for rescheduling.
-func (q *queue) ExpireHeaders(timeout time.Duration) map[string]int {
+func (q *queue) ExpireHeaders(peer string) int {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
-	return q.expire(timeout, q.headerPendPool, q.headerTaskQueue, headerTimeoutMeter)
+	headerTimeoutMeter.Mark(1)
+	return q.expire(peer, q.headerPendPool, q.headerTaskQueue)
 }
 
 // ExpireBodies checks for in flight block body requests that exceeded a timeout
 // allowance, canceling them and returning the responsible peers for penalisation.
-func (q *queue) ExpireBodies(timeout time.Duration) map[string]int {
+func (q *queue) ExpireBodies(peer string) int {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
-	return q.expire(timeout, q.blockPendPool, q.blockTaskQueue, bodyTimeoutMeter)
+	bodyTimeoutMeter.Mark(1)
+	return q.expire(peer, q.blockPendPool, q.blockTaskQueue)
 }
 
 // ExpireReceipts checks for in flight receipt requests that exceeded a timeout
 // allowance, canceling them and returning the responsible peers for penalisation.
-func (q *queue) ExpireReceipts(timeout time.Duration) map[string]int {
+func (q *queue) ExpireReceipts(peer string) int {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
-	return q.expire(timeout, q.receiptPendPool, q.receiptTaskQueue, receiptTimeoutMeter)
+	receiptTimeoutMeter.Mark(1)
+	return q.expire(peer, q.receiptPendPool, q.receiptTaskQueue)
 }
 
-// expire is the generic check that move expired tasks from a pending pool back
+// expire is the generic check that moves a specific expired task from a pending
-// into a task pool, returning all entities caught with expired tasks.
+// pool back into a task pool.
 //
-// Note, this method expects the queue lock to be already held. The
+// Note, this method expects the queue lock to be already held. The reason the
-// reason the lock is not obtained in here is because the parameters already need
+// lock is not obtained in here is that the parameters already need to access
-// to access the queue, so they already need a lock anyway.
+// the queue, so they already need a lock anyway.
-func (q *queue) expire(timeout time.Duration, pendPool map[string]*fetchRequest, taskQueue *prque.Prque, timeoutMeter metrics.Meter) map[string]int {
+func (q *queue) expire(peer string, pendPool map[string]*fetchRequest, taskQueue *prque.Prque) int {
-	// Iterate over the expired requests and return each to the queue
+	// Retrieve the request being expired and log an error if it's non-existnet,
-	expiries := make(map[string]int)
+	// as there's no order of events that should lead to such expirations.
-	for id, request := range pendPool {
+	req := pendPool[peer]
-		if time.Since(request.Time) > timeout {
+	if req == nil {
-			// Update the metrics with the timeout
+		log.Error("Expired request does not exist", "peer", peer)
-			timeoutMeter.Mark(1)
+		return 0
-
-			// Return any non satisfied requests to the pool
-			if request.From > 0 {
-				taskQueue.Push(request.From, -int64(request.From))
 	}
-			for _, header := range request.Headers {
+	delete(pendPool, peer)
+
+	// Return any non-satisfied requests to the pool
+	if req.From > 0 {
+		taskQueue.Push(req.From, -int64(req.From))
+	}
+	for _, header := range req.Headers {
 		taskQueue.Push(header, -int64(header.Number.Uint64()))
 	}
-			// Add the peer to the expiry report along the number of failed requests
+	return len(req.Headers)
-			expiries[id] = len(request.Headers)
-
-			// Remove the expired requests from the pending pool directly
-			delete(pendPool, id)
-		}
-	}
-	return expiries
 }
 
 // DeliverHeaders injects a header retrieval response into the header results
@@ -684,7 +654,7 @@ func (q *queue) expire(timeout time.Duration, pendPool map[string]*fetchRequest,
 // if they do not map correctly to the skeleton.
 //
 // If the headers are accepted, the method makes an attempt to deliver the set
-// of ready headers to the processor to keep the pipeline full. However it will
+// of ready headers to the processor to keep the pipeline full. However, it will
 // not block to prevent stalling other pending deliveries.
 func (q *queue) DeliverHeaders(id string, headers []*types.Header, headerProcCh chan []*types.Header) (int, error) {
 	q.lock.Lock()
@@ -700,11 +670,14 @@ func (q *queue) DeliverHeaders(id string, headers []*types.Header, headerProcCh
 	// Short circuit if the data was never requested
 	request := q.headerPendPool[id]
 	if request == nil {
+		headerDropMeter.Mark(int64(len(headers)))
 		return 0, errNoFetchesPending
 	}
-	headerReqTimer.UpdateSince(request.Time)
 	delete(q.headerPendPool, id)
 
+	headerReqTimer.UpdateSince(request.Time)
+	headerInMeter.Mark(int64(len(headers)))
+
 	// Ensure headers can be mapped onto the skeleton chain
 	target := q.headerTaskPool[request.From].Hash()
 
@@ -739,6 +712,7 @@ func (q *queue) DeliverHeaders(id string, headers []*types.Header, headerProcCh
 	// If the batch of headers wasn't accepted, mark as unavailable
 	if !accepted {
 		logger.Trace("Skeleton filling not accepted", "from", request.From)
+		headerDropMeter.Mark(int64(len(headers)))
 
 		miss := q.headerPeerMiss[id]
 		if miss == nil {
@@ -783,6 +757,7 @@ func (q *queue) DeliverHeaders(id string, headers []*types.Header, headerProcCh
 func (q *queue) DeliverBodies(id string, txLists [][]*types.Transaction, uncleLists [][]*types.Header) (int, error) {
 	q.lock.Lock()
 	defer q.lock.Unlock()
+
 	trieHasher := trie.NewStackTrie(nil)
 	validate := func(index int, header *types.Header) error {
 		if types.DeriveSha(types.Transactions(txLists[index]), trieHasher) != header.TxHash {
@@ -800,7 +775,7 @@ func (q *queue) DeliverBodies(id string, txLists [][]*types.Transaction, uncleLi
 		result.SetBodyDone()
 	}
 	return q.deliver(id, q.blockTaskPool, q.blockTaskQueue, q.blockPendPool,
-		bodyReqTimer, len(txLists), validate, reconstruct)
+		bodyReqTimer, bodyInMeter, bodyDropMeter, len(txLists), validate, reconstruct)
 }
 
 // DeliverReceipts injects a receipt retrieval response into the results queue.
@@ -809,6 +784,7 @@ func (q *queue) DeliverBodies(id string, txLists [][]*types.Transaction, uncleLi
 func (q *queue) DeliverReceipts(id string, receiptList [][]*types.Receipt) (int, error) {
 	q.lock.Lock()
 	defer q.lock.Unlock()
+
 	trieHasher := trie.NewStackTrie(nil)
 	validate := func(index int, header *types.Header) error {
 		if types.DeriveSha(types.Receipts(receiptList[index]), trieHasher) != header.ReceiptHash {
@@ -821,7 +797,7 @@ func (q *queue) DeliverReceipts(id string, receiptList [][]*types.Receipt) (int,
 		result.SetReceiptsDone()
 	}
 	return q.deliver(id, q.receiptTaskPool, q.receiptTaskQueue, q.receiptPendPool,
-		receiptReqTimer, len(receiptList), validate, reconstruct)
+		receiptReqTimer, receiptInMeter, receiptDropMeter, len(receiptList), validate, reconstruct)
 }
 
 // deliver injects a data retrieval response into the results queue.
@@ -830,18 +806,22 @@ func (q *queue) DeliverReceipts(id string, receiptList [][]*types.Receipt) (int,
 // reason this lock is not obtained in here is because the parameters already need
 // to access the queue, so they already need a lock anyway.
 func (q *queue) deliver(id string, taskPool map[common.Hash]*types.Header,
-	taskQueue *prque.Prque, pendPool map[string]*fetchRequest, reqTimer metrics.Timer,
+	taskQueue *prque.Prque, pendPool map[string]*fetchRequest,
+	reqTimer metrics.Timer, resInMeter metrics.Meter, resDropMeter metrics.Meter,
 	results int, validate func(index int, header *types.Header) error,
 	reconstruct func(index int, result *fetchResult)) (int, error) {
 
 	// Short circuit if the data was never requested
 	request := pendPool[id]
 	if request == nil {
+		resDropMeter.Mark(int64(results))
 		return 0, errNoFetchesPending
 	}
-	reqTimer.UpdateSince(request.Time)
 	delete(pendPool, id)
 
+	reqTimer.UpdateSince(request.Time)
+	resInMeter.Mark(int64(results))
+
 	// If no data items were retrieved, mark them as unavailable for the origin peer
 	if results == 0 {
 		for _, header := range request.Headers {
@@ -883,6 +863,8 @@ func (q *queue) deliver(id string, taskPool map[common.Hash]*types.Header,
 		delete(taskPool, hashes[accepted])
 		accepted++
 	}
+	resDropMeter.Mark(int64(results - accepted))
+
 	// Return all failed or missing fetches to the queue
 	for _, header := range request.Headers[accepted:] {
 		taskQueue.Push(header, -int64(header.Number.Uint64()))

eth/downloader/queue_test.go

@@ -104,7 +104,7 @@ func TestBasics(t *testing.T) {
 	if !q.Idle() {
 		t.Errorf("new queue should be idle")
 	}
-	q.Prepare(1, FastSync)
+	q.Prepare(1, SnapSync)
 	if res := q.Results(false); len(res) != 0 {
 		t.Fatal("new queue should have 0 results")
 	}
@@ -114,7 +114,7 @@ func TestBasics(t *testing.T) {
 	if q.Idle() {
 		t.Errorf("queue should not be idle")
 	}
-	if got, exp := q.PendingBlocks(), chain.Len(); got != exp {
+	if got, exp := q.PendingBodies(), chain.Len(); got != exp {
 		t.Errorf("wrong pending block count, got %d, exp %d", got, exp)
 	}
 	// Only non-empty receipts get added to task-queue
@@ -197,13 +197,13 @@ func TestEmptyBlocks(t *testing.T) {
 
 	q := newQueue(10, 10)
 
-	q.Prepare(1, FastSync)
+	q.Prepare(1, SnapSync)
 	// Schedule a batch of headers
 	q.Schedule(emptyChain.headers(), 1)
 	if q.Idle() {
 		t.Errorf("queue should not be idle")
 	}
-	if got, exp := q.PendingBlocks(), len(emptyChain.blocks); got != exp {
+	if got, exp := q.PendingBodies(), len(emptyChain.blocks); got != exp {
 		t.Errorf("wrong pending block count, got %d, exp %d", got, exp)
 	}
 	if got, exp := q.PendingReceipts(), 0; got != exp {
@@ -272,7 +272,7 @@ func XTestDelivery(t *testing.T) {
 	}
 	q := newQueue(10, 10)
 	var wg sync.WaitGroup
-	q.Prepare(1, FastSync)
+	q.Prepare(1, SnapSync)
 	wg.Add(1)
 	go func() {
 		// deliver headers

eth/downloader/statesync.go

@@ -17,48 +17,12 @@
 package downloader
 
 import (
-	"fmt"
 	"sync"
-	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/rawdb"
-	"github.com/ethereum/go-ethereum/core/state"
-	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/log"
-	"github.com/ethereum/go-ethereum/trie"
-	"golang.org/x/crypto/sha3"
 )
 
-// stateReq represents a batch of state fetch requests grouped together into
-// a single data retrieval network packet.
-type stateReq struct {
-	nItems    uint16                    // Number of items requested for download (max is 384, so uint16 is sufficient)
-	trieTasks map[common.Hash]*trieTask // Trie node download tasks to track previous attempts
-	codeTasks map[common.Hash]*codeTask // Byte code download tasks to track previous attempts
-	timeout   time.Duration             // Maximum round trip time for this to complete
-	timer     *time.Timer               // Timer to fire when the RTT timeout expires
-	peer      *peerConnection           // Peer that we're requesting from
-	delivered time.Time                 // Time when the packet was delivered (independent when we process it)
-	response  [][]byte                  // Response data of the peer (nil for timeouts)
-	dropped   bool                      // Flag whether the peer dropped off early
-}
-
-// timedOut returns if this request timed out.
-func (req *stateReq) timedOut() bool {
-	return req.response == nil
-}
-
-// stateSyncStats is a collection of progress stats to report during a state trie
-// sync to RPC requests as well as to display in user logs.
-type stateSyncStats struct {
-	processed  uint64 // Number of state entries processed
-	duplicate  uint64 // Number of state entries downloaded twice
-	unexpected uint64 // Number of non-requested state entries received
-	pending    uint64 // Number of still pending state entries
-}
-
 // syncState starts downloading state with the given root hash.
 func (d *Downloader) syncState(root common.Hash) *stateSync {
 	// Create the state sync
@@ -85,8 +49,6 @@ func (d *Downloader) stateFetcher() {
 			for next := s; next != nil; {
 				next = d.runStateSync(next)
 			}
-		case <-d.stateCh:
-			// Ignore state responses while no sync is running.
 		case <-d.quitCh:
 			return
 		}
@@ -96,162 +58,19 @@ func (d *Downloader) stateFetcher() {
 // runStateSync runs a state synchronisation until it completes or another root
 // hash is requested to be switched over to.
 func (d *Downloader) runStateSync(s *stateSync) *stateSync {
-	var (
-		active   = make(map[string]*stateReq) // Currently in-flight requests
-		finished []*stateReq                  // Completed or failed requests
-		timeout  = make(chan *stateReq)       // Timed out active requests
-	)
 	log.Trace("State sync starting", "root", s.root)
 
-	defer func() {
-		// Cancel active request timers on exit. Also set peers to idle so they're
-		// available for the next sync.
-		for _, req := range active {
-			req.timer.Stop()
-			req.peer.SetNodeDataIdle(int(req.nItems), time.Now())
-		}
-	}()
 	go s.run()
 	defer s.Cancel()
 
-	// Listen for peer departure events to cancel assigned tasks
-	peerDrop := make(chan *peerConnection, 1024)
-	peerSub := s.d.peers.SubscribePeerDrops(peerDrop)
-	defer peerSub.Unsubscribe()
-
 	for {
-		// Enable sending of the first buffered element if there is one.
-		var (
-			deliverReq   *stateReq
-			deliverReqCh chan *stateReq
-		)
-		if len(finished) > 0 {
-			deliverReq = finished[0]
-			deliverReqCh = s.deliver
-		}
-
 		select {
-		// The stateSync lifecycle:
 		case next := <-d.stateSyncStart:
-			d.spindownStateSync(active, finished, timeout, peerDrop)
 			return next
 
 		case <-s.done:
-			d.spindownStateSync(active, finished, timeout, peerDrop)
 			return nil
-
-		// Send the next finished request to the current sync:
-		case deliverReqCh <- deliverReq:
-			// Shift out the first request, but also set the emptied slot to nil for GC
-			copy(finished, finished[1:])
-			finished[len(finished)-1] = nil
-			finished = finished[:len(finished)-1]
-
-		// Handle incoming state packs:
-		case pack := <-d.stateCh:
-			// Discard any data not requested (or previously timed out)
-			req := active[pack.PeerId()]
-			if req == nil {
-				log.Debug("Unrequested node data", "peer", pack.PeerId(), "len", pack.Items())
-				continue
 		}
-			// Finalize the request and queue up for processing
-			req.timer.Stop()
-			req.response = pack.(*statePack).states
-			req.delivered = time.Now()
-
-			finished = append(finished, req)
-			delete(active, pack.PeerId())
-
-		// Handle dropped peer connections:
-		case p := <-peerDrop:
-			// Skip if no request is currently pending
-			req := active[p.id]
-			if req == nil {
-				continue
-			}
-			// Finalize the request and queue up for processing
-			req.timer.Stop()
-			req.dropped = true
-			req.delivered = time.Now()
-
-			finished = append(finished, req)
-			delete(active, p.id)
-
-		// Handle timed-out requests:
-		case req := <-timeout:
-			// If the peer is already requesting something else, ignore the stale timeout.
-			// This can happen when the timeout and the delivery happens simultaneously,
-			// causing both pathways to trigger.
-			if active[req.peer.id] != req {
-				continue
-			}
-			req.delivered = time.Now()
-			// Move the timed out data back into the download queue
-			finished = append(finished, req)
-			delete(active, req.peer.id)
-
-		// Track outgoing state requests:
-		case req := <-d.trackStateReq:
-			// If an active request already exists for this peer, we have a problem. In
-			// theory the trie node schedule must never assign two requests to the same
-			// peer. In practice however, a peer might receive a request, disconnect and
-			// immediately reconnect before the previous times out. In this case the first
-			// request is never honored, alas we must not silently overwrite it, as that
-			// causes valid requests to go missing and sync to get stuck.
-			if old := active[req.peer.id]; old != nil {
-				log.Warn("Busy peer assigned new state fetch", "peer", old.peer.id)
-				// Move the previous request to the finished set
-				old.timer.Stop()
-				old.dropped = true
-				old.delivered = time.Now()
-				finished = append(finished, old)
-			}
-			// Start a timer to notify the sync loop if the peer stalled.
-			req.timer = time.AfterFunc(req.timeout, func() {
-				timeout <- req
-			})
-			active[req.peer.id] = req
-		}
-	}
-}
-
-// spindownStateSync 'drains' the outstanding requests; some will be delivered and other
-// will time out. This is to ensure that when the next stateSync starts working, all peers
-// are marked as idle and de facto _are_ idle.
-func (d *Downloader) spindownStateSync(active map[string]*stateReq, finished []*stateReq, timeout chan *stateReq, peerDrop chan *peerConnection) {
-	log.Trace("State sync spinning down", "active", len(active), "finished", len(finished))
-	for len(active) > 0 {
-		var (
-			req    *stateReq
-			reason string
-		)
-		select {
-		// Handle (drop) incoming state packs:
-		case pack := <-d.stateCh:
-			req = active[pack.PeerId()]
-			reason = "delivered"
-		// Handle dropped peer connections:
-		case p := <-peerDrop:
-			req = active[p.id]
-			reason = "peerdrop"
-		// Handle timed-out requests:
-		case req = <-timeout:
-			reason = "timeout"
-		}
-		if req == nil {
-			continue
-		}
-		req.peer.log.Trace("State peer marked idle (spindown)", "req.items", int(req.nItems), "reason", reason)
-		req.timer.Stop()
-		delete(active, req.peer.id)
-		req.peer.SetNodeDataIdle(int(req.nItems), time.Now())
-	}
-	// The 'finished' set contains deliveries that we were going to pass to processing.
-	// Those are now moot, but we still need to set those peers as idle, which would
-	// otherwise have been done after processing
-	for _, req := range finished {
-		req.peer.SetNodeDataIdle(int(req.nItems), time.Now())
 	}
 }
 
@@ -259,50 +78,21 @@ func (d *Downloader) spindownStateSync(active map[string]*stateReq, finished []*
 // by a given state root.
 type stateSync struct {
 	d    *Downloader // Downloader instance to access and manage current peerset
-
 	root common.Hash // State root currently being synced
-	sched  *trie.Sync         // State trie sync scheduler defining the tasks
-	keccak crypto.KeccakState // Keccak256 hasher to verify deliveries with
-
-	trieTasks map[common.Hash]*trieTask // Set of trie node tasks currently queued for retrieval
-	codeTasks map[common.Hash]*codeTask // Set of byte code tasks currently queued for retrieval
-
-	numUncommitted   int
-	bytesUncommitted int
 
 	started    chan struct{} // Started is signalled once the sync loop starts
-
-	deliver    chan *stateReq // Delivery channel multiplexing peer responses
 	cancel     chan struct{} // Channel to signal a termination request
 	cancelOnce sync.Once     // Ensures cancel only ever gets called once
 	done       chan struct{} // Channel to signal termination completion
 	err        error         // Any error hit during sync (set before completion)
 }
 
-// trieTask represents a single trie node download task, containing a set of
-// peers already attempted retrieval from to detect stalled syncs and abort.
-type trieTask struct {
-	path     [][]byte
-	attempts map[string]struct{}
-}
-
-// codeTask represents a single byte code download task, containing a set of
-// peers already attempted retrieval from to detect stalled syncs and abort.
-type codeTask struct {
-	attempts map[string]struct{}
-}
-
 // newStateSync creates a new state trie download scheduler. This method does not
 // yet start the sync. The user needs to call run to initiate.
 func newStateSync(d *Downloader, root common.Hash) *stateSync {
 	return &stateSync{
 		d:       d,
 		root:    root,
-		sched:     state.NewStateSync(root, d.stateDB, d.stateBloom, nil),
-		keccak:    sha3.NewLegacyKeccak256().(crypto.KeccakState),
-		trieTasks: make(map[common.Hash]*trieTask),
-		codeTasks: make(map[common.Hash]*codeTask),
-		deliver:   make(chan *stateReq),
 		cancel:  make(chan struct{}),
 		done:    make(chan struct{}),
 		started: make(chan struct{}),
@@ -314,11 +104,7 @@ func newStateSync(d *Downloader, root common.Hash) *stateSync {
 // finish.
 func (s *stateSync) run() {
 	close(s.started)
-	if s.d.snapSync {
 	s.err = s.d.SnapSyncer.Sync(s.root, s.cancel)
-	} else {
-		s.err = s.loop()
-	}
 	close(s.done)
 }
 
@@ -335,281 +121,3 @@ func (s *stateSync) Cancel() error {
 	})
 	return s.Wait()
 }
-
-// loop is the main event loop of a state trie sync. It it responsible for the
-// assignment of new tasks to peers (including sending it to them) as well as
-// for the processing of inbound data. Note, that the loop does not directly
-// receive data from peers, rather those are buffered up in the downloader and
-// pushed here async. The reason is to decouple processing from data receipt
-// and timeouts.
-func (s *stateSync) loop() (err error) {
-	// Listen for new peer events to assign tasks to them
-	newPeer := make(chan *peerConnection, 1024)
-	peerSub := s.d.peers.SubscribeNewPeers(newPeer)
-	defer peerSub.Unsubscribe()
-	defer func() {
-		cerr := s.commit(true)
-		if err == nil {
-			err = cerr
-		}
-	}()
-
-	// Keep assigning new tasks until the sync completes or aborts
-	for s.sched.Pending() > 0 {
-		if err = s.commit(false); err != nil {
-			return err
-		}
-		s.assignTasks()
-		// Tasks assigned, wait for something to happen
-		select {
-		case <-newPeer:
-			// New peer arrived, try to assign it download tasks
-
-		case <-s.cancel:
-			return errCancelStateFetch
-
-		case <-s.d.cancelCh:
-			return errCanceled
-
-		case req := <-s.deliver:
-			// Response, disconnect or timeout triggered, drop the peer if stalling
-			log.Trace("Received node data response", "peer", req.peer.id, "count", len(req.response), "dropped", req.dropped, "timeout", !req.dropped && req.timedOut())
-			if req.nItems <= 2 && !req.dropped && req.timedOut() {
-				// 2 items are the minimum requested, if even that times out, we've no use of
-				// this peer at the moment.
-				log.Warn("Stalling state sync, dropping peer", "peer", req.peer.id)
-				if s.d.dropPeer == nil {
-					// The dropPeer method is nil when `--copydb` is used for a local copy.
-					// Timeouts can occur if e.g. compaction hits at the wrong time, and can be ignored
-					req.peer.log.Warn("Downloader wants to drop peer, but peerdrop-function is not set", "peer", req.peer.id)
-				} else {
-					s.d.dropPeer(req.peer.id)
-
-					// If this peer was the master peer, abort sync immediately
-					s.d.cancelLock.RLock()
-					master := req.peer.id == s.d.cancelPeer
-					s.d.cancelLock.RUnlock()
-
-					if master {
-						s.d.cancel()
-						return errTimeout
-					}
-				}
-			}
-			// Process all the received blobs and check for stale delivery
-			delivered, err := s.process(req)
-			req.peer.SetNodeDataIdle(delivered, req.delivered)
-			if err != nil {
-				log.Warn("Node data write error", "err", err)
-				return err
-			}
-		}
-	}
-	return nil
-}
-
-func (s *stateSync) commit(force bool) error {
-	if !force && s.bytesUncommitted < ethdb.IdealBatchSize {
-		return nil
-	}
-	start := time.Now()
-	b := s.d.stateDB.NewBatch()
-	if err := s.sched.Commit(b); err != nil {
-		return err
-	}
-	if err := b.Write(); err != nil {
-		return fmt.Errorf("DB write error: %v", err)
-	}
-	s.updateStats(s.numUncommitted, 0, 0, time.Since(start))
-	s.numUncommitted = 0
-	s.bytesUncommitted = 0
-	return nil
-}
-
-// assignTasks attempts to assign new tasks to all idle peers, either from the
-// batch currently being retried, or fetching new data from the trie sync itself.
-func (s *stateSync) assignTasks() {
-	// Iterate over all idle peers and try to assign them state fetches
-	peers, _ := s.d.peers.NodeDataIdlePeers()
-	for _, p := range peers {
-		// Assign a batch of fetches proportional to the estimated latency/bandwidth
-		cap := p.NodeDataCapacity(s.d.peers.rates.TargetRoundTrip())
-		req := &stateReq{peer: p, timeout: s.d.peers.rates.TargetTimeout()}
-
-		nodes, _, codes := s.fillTasks(cap, req)
-
-		// If the peer was assigned tasks to fetch, send the network request
-		if len(nodes)+len(codes) > 0 {
-			req.peer.log.Trace("Requesting batch of state data", "nodes", len(nodes), "codes", len(codes), "root", s.root)
-			select {
-			case s.d.trackStateReq <- req:
-				req.peer.FetchNodeData(append(nodes, codes...)) // Unified retrieval under eth/6x
-			case <-s.cancel:
-			case <-s.d.cancelCh:
-			}
-		}
-	}
-}
-
-// fillTasks fills the given request object with a maximum of n state download
-// tasks to send to the remote peer.
-func (s *stateSync) fillTasks(n int, req *stateReq) (nodes []common.Hash, paths []trie.SyncPath, codes []common.Hash) {
-	// Refill available tasks from the scheduler.
-	if fill := n - (len(s.trieTasks) + len(s.codeTasks)); fill > 0 {
-		nodes, paths, codes := s.sched.Missing(fill)
-		for i, hash := range nodes {
-			s.trieTasks[hash] = &trieTask{
-				path:     paths[i],
-				attempts: make(map[string]struct{}),
-			}
-		}
-		for _, hash := range codes {
-			s.codeTasks[hash] = &codeTask{
-				attempts: make(map[string]struct{}),
-			}
-		}
-	}
-	// Find tasks that haven't been tried with the request's peer. Prefer code
-	// over trie nodes as those can be written to disk and forgotten about.
-	nodes = make([]common.Hash, 0, n)
-	paths = make([]trie.SyncPath, 0, n)
-	codes = make([]common.Hash, 0, n)
-
-	req.trieTasks = make(map[common.Hash]*trieTask, n)
-	req.codeTasks = make(map[common.Hash]*codeTask, n)
-
-	for hash, t := range s.codeTasks {
-		// Stop when we've gathered enough requests
-		if len(nodes)+len(codes) == n {
-			break
-		}
-		// Skip any requests we've already tried from this peer
-		if _, ok := t.attempts[req.peer.id]; ok {
-			continue
-		}
-		// Assign the request to this peer
-		t.attempts[req.peer.id] = struct{}{}
-		codes = append(codes, hash)
-		req.codeTasks[hash] = t
-		delete(s.codeTasks, hash)
-	}
-	for hash, t := range s.trieTasks {
-		// Stop when we've gathered enough requests
-		if len(nodes)+len(codes) == n {
-			break
-		}
-		// Skip any requests we've already tried from this peer
-		if _, ok := t.attempts[req.peer.id]; ok {
-			continue
-		}
-		// Assign the request to this peer
-		t.attempts[req.peer.id] = struct{}{}
-
-		nodes = append(nodes, hash)
-		paths = append(paths, t.path)
-
-		req.trieTasks[hash] = t
-		delete(s.trieTasks, hash)
-	}
-	req.nItems = uint16(len(nodes) + len(codes))
-	return nodes, paths, codes
-}
-
-// process iterates over a batch of delivered state data, injecting each item
-// into a running state sync, re-queuing any items that were requested but not
-// delivered. Returns whether the peer actually managed to deliver anything of
-// value, and any error that occurred.
-func (s *stateSync) process(req *stateReq) (int, error) {
-	// Collect processing stats and update progress if valid data was received
-	duplicate, unexpected, successful := 0, 0, 0
-
-	defer func(start time.Time) {
-		if duplicate > 0 || unexpected > 0 {
-			s.updateStats(0, duplicate, unexpected, time.Since(start))
-		}
-	}(time.Now())
-
-	// Iterate over all the delivered data and inject one-by-one into the trie
-	for _, blob := range req.response {
-		hash, err := s.processNodeData(blob)
-		switch err {
-		case nil:
-			s.numUncommitted++
-			s.bytesUncommitted += len(blob)
-			successful++
-		case trie.ErrNotRequested:
-			unexpected++
-		case trie.ErrAlreadyProcessed:
-			duplicate++
-		default:
-			return successful, fmt.Errorf("invalid state node %s: %v", hash.TerminalString(), err)
-		}
-		// Delete from both queues (one delivery is enough for the syncer)
-		delete(req.trieTasks, hash)
-		delete(req.codeTasks, hash)
-	}
-	// Put unfulfilled tasks back into the retry queue
-	npeers := s.d.peers.Len()
-	for hash, task := range req.trieTasks {
-		// If the node did deliver something, missing items may be due to a protocol
-		// limit or a previous timeout + delayed delivery. Both cases should permit
-		// the node to retry the missing items (to avoid single-peer stalls).
-		if len(req.response) > 0 || req.timedOut() {
-			delete(task.attempts, req.peer.id)
-		}
-		// If we've requested the node too many times already, it may be a malicious
-		// sync where nobody has the right data. Abort.
-		if len(task.attempts) >= npeers {
-			return successful, fmt.Errorf("trie node %s failed with all peers (%d tries, %d peers)", hash.TerminalString(), len(task.attempts), npeers)
-		}
-		// Missing item, place into the retry queue.
-		s.trieTasks[hash] = task
-	}
-	for hash, task := range req.codeTasks {
-		// If the node did deliver something, missing items may be due to a protocol
-		// limit or a previous timeout + delayed delivery. Both cases should permit
-		// the node to retry the missing items (to avoid single-peer stalls).
-		if len(req.response) > 0 || req.timedOut() {
-			delete(task.attempts, req.peer.id)
-		}
-		// If we've requested the node too many times already, it may be a malicious
-		// sync where nobody has the right data. Abort.
-		if len(task.attempts) >= npeers {
-			return successful, fmt.Errorf("byte code %s failed with all peers (%d tries, %d peers)", hash.TerminalString(), len(task.attempts), npeers)
-		}
-		// Missing item, place into the retry queue.
-		s.codeTasks[hash] = task
-	}
-	return successful, nil
-}
-
-// processNodeData tries to inject a trie node data blob delivered from a remote
-// peer into the state trie, returning whether anything useful was written or any
-// error occurred.
-func (s *stateSync) processNodeData(blob []byte) (common.Hash, error) {
-	res := trie.SyncResult{Data: blob}
-	s.keccak.Reset()
-	s.keccak.Write(blob)
-	s.keccak.Read(res.Hash[:])
-	err := s.sched.Process(res)
-	return res.Hash, err
-}
-
-// updateStats bumps the various state sync progress counters and displays a log
-// message for the user to see.
-func (s *stateSync) updateStats(written, duplicate, unexpected int, duration time.Duration) {
-	s.d.syncStatsLock.Lock()
-	defer s.d.syncStatsLock.Unlock()
-
-	s.d.syncStatsState.pending = uint64(s.sched.Pending())
-	s.d.syncStatsState.processed += uint64(written)
-	s.d.syncStatsState.duplicate += uint64(duplicate)
-	s.d.syncStatsState.unexpected += uint64(unexpected)
-
-	if written > 0 || duplicate > 0 || unexpected > 0 {
-		log.Info("Imported new state entries", "count", written, "elapsed", common.PrettyDuration(duration), "processed", s.d.syncStatsState.processed, "pending", s.d.syncStatsState.pending, "trieretry", len(s.trieTasks), "coderetry", len(s.codeTasks), "duplicate", s.d.syncStatsState.duplicate, "unexpected", s.d.syncStatsState.unexpected)
-	}
-	if written > 0 {
-		rawdb.WriteFastTrieProgress(s.d.stateDB, s.d.syncStatsState.processed)
-	}
-}

eth/downloader/testchain_test.go

@@ -20,12 +20,14 @@ import (
 	"fmt"
 	"math/big"
 	"sync"
+	"time"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/params"
 )
@@ -39,73 +41,110 @@ var (
 )
 
 // The common prefix of all test chains:
-var testChainBase = newTestChain(blockCacheMaxItems+200, testGenesis)
+var testChainBase *testChain
 
 // Different forks on top of the base chain:
 var testChainForkLightA, testChainForkLightB, testChainForkHeavy *testChain
 
+var pregenerated bool
+
 func init() {
+	// Reduce some of the parameters to make the tester faster
+	fullMaxForkAncestry = 10000
+	lightMaxForkAncestry = 10000
+	blockCacheMaxItems = 1024
+	fsHeaderSafetyNet = 256
+	fsHeaderContCheck = 500 * time.Millisecond
+
+	testChainBase = newTestChain(blockCacheMaxItems+200, testGenesis)
+
 	var forkLen = int(fullMaxForkAncestry + 50)
 	var wg sync.WaitGroup
+
+	// Generate the test chains to seed the peers with
 	wg.Add(3)
 	go func() { testChainForkLightA = testChainBase.makeFork(forkLen, false, 1); wg.Done() }()
 	go func() { testChainForkLightB = testChainBase.makeFork(forkLen, false, 2); wg.Done() }()
 	go func() { testChainForkHeavy = testChainBase.makeFork(forkLen, true, 3); wg.Done() }()
 	wg.Wait()
+
+	// Generate the test peers used by the tests to avoid overloading during testing.
+	// These seemingly random chains are used in various downloader tests. We're just
+	// pre-generating them here.
+	chains := []*testChain{
+		testChainBase,
+		testChainForkLightA,
+		testChainForkLightB,
+		testChainForkHeavy,
+		testChainBase.shorten(1),
+		testChainBase.shorten(blockCacheMaxItems - 15),
+		testChainBase.shorten((blockCacheMaxItems - 15) / 2),
+		testChainBase.shorten(blockCacheMaxItems - 15 - 5),
+		testChainBase.shorten(MaxHeaderFetch),
+		testChainBase.shorten(800),
+		testChainBase.shorten(800 / 2),
+		testChainBase.shorten(800 / 3),
+		testChainBase.shorten(800 / 4),
+		testChainBase.shorten(800 / 5),
+		testChainBase.shorten(800 / 6),
+		testChainBase.shorten(800 / 7),
+		testChainBase.shorten(800 / 8),
+		testChainBase.shorten(3*fsHeaderSafetyNet + 256 + fsMinFullBlocks),
+		testChainBase.shorten(fsMinFullBlocks + 256 - 1),
+		testChainForkLightA.shorten(len(testChainBase.blocks) + 80),
+		testChainForkLightB.shorten(len(testChainBase.blocks) + 81),
+		testChainForkLightA.shorten(len(testChainBase.blocks) + MaxHeaderFetch),
+		testChainForkLightB.shorten(len(testChainBase.blocks) + MaxHeaderFetch),
+		testChainForkHeavy.shorten(len(testChainBase.blocks) + 79),
+	}
+	wg.Add(len(chains))
+	for _, chain := range chains {
+		go func(blocks []*types.Block) {
+			newTestBlockchain(blocks)
+			wg.Done()
+		}(chain.blocks[1:])
+	}
+	wg.Wait()
+
+	// Mark the chains pregenerated. Generating a new one will lead to a panic.
+	pregenerated = true
 }
 
 type testChain struct {
-	genesis  *types.Block
+	blocks []*types.Block
-	chain    []common.Hash
-	headerm  map[common.Hash]*types.Header
-	blockm   map[common.Hash]*types.Block
-	receiptm map[common.Hash][]*types.Receipt
-	tdm      map[common.Hash]*big.Int
 }
 
 // newTestChain creates a blockchain of the given length.
 func newTestChain(length int, genesis *types.Block) *testChain {
-	tc := new(testChain).copy(length)
+	tc := &testChain{
-	tc.genesis = genesis
+		blocks: []*types.Block{genesis},
-	tc.chain = append(tc.chain, genesis.Hash())
+	}
-	tc.headerm[tc.genesis.Hash()] = tc.genesis.Header()
-	tc.tdm[tc.genesis.Hash()] = tc.genesis.Difficulty()
-	tc.blockm[tc.genesis.Hash()] = tc.genesis
 	tc.generate(length-1, 0, genesis, false)
 	return tc
 }
 
 // makeFork creates a fork on top of the test chain.
 func (tc *testChain) makeFork(length int, heavy bool, seed byte) *testChain {
-	fork := tc.copy(tc.len() + length)
+	fork := tc.copy(len(tc.blocks) + length)
-	fork.generate(length, seed, tc.headBlock(), heavy)
+	fork.generate(length, seed, tc.blocks[len(tc.blocks)-1], heavy)
 	return fork
 }
 
 // shorten creates a copy of the chain with the given length. It panics if the
 // length is longer than the number of available blocks.
 func (tc *testChain) shorten(length int) *testChain {
-	if length > tc.len() {
+	if length > len(tc.blocks) {
-		panic(fmt.Errorf("can't shorten test chain to %d blocks, it's only %d blocks long", length, tc.len()))
+		panic(fmt.Errorf("can't shorten test chain to %d blocks, it's only %d blocks long", length, len(tc.blocks)))
 	}
 	return tc.copy(length)
 }
 
 func (tc *testChain) copy(newlen int) *testChain {
-	cpy := &testChain{
+	if newlen > len(tc.blocks) {
-		genesis:  tc.genesis,
+		newlen = len(tc.blocks)
-		headerm:  make(map[common.Hash]*types.Header, newlen),
-		blockm:   make(map[common.Hash]*types.Block, newlen),
-		receiptm: make(map[common.Hash][]*types.Receipt, newlen),
-		tdm:      make(map[common.Hash]*big.Int, newlen),
 	}
-	for i := 0; i < len(tc.chain) && i < newlen; i++ {
+	cpy := &testChain{
-		hash := tc.chain[i]
+		blocks: append([]*types.Block{}, tc.blocks[:newlen]...),
-		cpy.chain = append(cpy.chain, tc.chain[i])
-		cpy.tdm[hash] = tc.tdm[hash]
-		cpy.blockm[hash] = tc.blockm[hash]
-		cpy.headerm[hash] = tc.headerm[hash]
-		cpy.receiptm[hash] = tc.receiptm[hash]
 	}
 	return cpy
 }
@@ -115,17 +154,14 @@ func (tc *testChain) copy(newlen int) *testChain {
 // contains a transaction and every 5th an uncle to allow testing correct block
 // reassembly.
 func (tc *testChain) generate(n int, seed byte, parent *types.Block, heavy bool) {
-	// start := time.Now()
+	blocks, _ := core.GenerateChain(params.TestChainConfig, parent, ethash.NewFaker(), testDB, n, func(i int, block *core.BlockGen) {
-	// defer func() { fmt.Printf("test chain generated in %v\n", time.Since(start)) }()
-
-	blocks, receipts := core.GenerateChain(params.TestChainConfig, parent, ethash.NewFaker(), testDB, n, func(i int, block *core.BlockGen) {
 		block.SetCoinbase(common.Address{seed})
 		// If a heavy chain is requested, delay blocks to raise difficulty
 		if heavy {
-			block.OffsetTime(-1)
+			block.OffsetTime(-9)
 		}
 		// Include transactions to the miner to make blocks more interesting.
-		if parent == tc.genesis && i%22 == 0 {
+		if parent == tc.blocks[0] && i%22 == 0 {
 			signer := types.MakeSigner(params.TestChainConfig, block.Number())
 			tx, err := types.SignTx(types.NewTransaction(block.TxNonce(testAddress), common.Address{seed}, big.NewInt(1000), params.TxGas, block.BaseFee(), nil), signer, testKey)
 			if err != nil {
@@ -136,95 +172,56 @@ func (tc *testChain) generate(n int, seed byte, parent *types.Block, heavy bool)
 		// if the block number is a multiple of 5, add a bonus uncle to the block
 		if i > 0 && i%5 == 0 {
 			block.AddUncle(&types.Header{
-				ParentHash: block.PrevBlock(i - 1).Hash(),
+				ParentHash: block.PrevBlock(i - 2).Hash(),
 				Number:     big.NewInt(block.Number().Int64() - 1),
 			})
 		}
 	})
-
+	tc.blocks = append(tc.blocks, blocks...)
-	// Convert the block-chain into a hash-chain and header/block maps
-	td := new(big.Int).Set(tc.td(parent.Hash()))
-	for i, b := range blocks {
-		td := td.Add(td, b.Difficulty())
-		hash := b.Hash()
-		tc.chain = append(tc.chain, hash)
-		tc.blockm[hash] = b
-		tc.headerm[hash] = b.Header()
-		tc.receiptm[hash] = receipts[i]
-		tc.tdm[hash] = new(big.Int).Set(td)
-	}
 }
 
-// len returns the total number of blocks in the chain.
+var (
-func (tc *testChain) len() int {
+	testBlockchains     = make(map[common.Hash]*testBlockchain)
-	return len(tc.chain)
+	testBlockchainsLock sync.Mutex
+)
+
+type testBlockchain struct {
+	chain *core.BlockChain
+	gen   sync.Once
 }
 
-// headBlock returns the head of the chain.
+// newTestBlockchain creates a blockchain database built by running the given blocks,
-func (tc *testChain) headBlock() *types.Block {
+// either actually running them, or reusing a previously created one. The returned
-	return tc.blockm[tc.chain[len(tc.chain)-1]]
+// chains are *shared*, so *do not* mutate them.
-}
+func newTestBlockchain(blocks []*types.Block) *core.BlockChain {
+	// Retrieve an existing database, or create a new one
+	head := testGenesis.Hash()
+	if len(blocks) > 0 {
+		head = blocks[len(blocks)-1].Hash()
+	}
+	testBlockchainsLock.Lock()
+	if _, ok := testBlockchains[head]; !ok {
+		testBlockchains[head] = new(testBlockchain)
+	}
+	tbc := testBlockchains[head]
+	testBlockchainsLock.Unlock()
 
-// td returns the total difficulty of the given block.
+	// Ensure that the database is generated
-func (tc *testChain) td(hash common.Hash) *big.Int {
+	tbc.gen.Do(func() {
-	return tc.tdm[hash]
+		if pregenerated {
-}
+			panic("Requested chain generation outside of init")
+		}
+		db := rawdb.NewMemoryDatabase()
+		core.GenesisBlockForTesting(db, testAddress, big.NewInt(1000000000000000))
 
-// headersByHash returns headers in order from the given hash.
+		chain, err := core.NewBlockChain(db, nil, params.TestChainConfig, ethash.NewFaker(), vm.Config{}, nil, nil)
-func (tc *testChain) headersByHash(origin common.Hash, amount int, skip int, reverse bool) []*types.Header {
+		if err != nil {
-	num, _ := tc.hashToNumber(origin)
+			panic(err)
-	return tc.headersByNumber(num, amount, skip, reverse)
+		}
-}
+		if n, err := chain.InsertChain(blocks); err != nil {
-
+			panic(fmt.Sprintf("block %d: %v", n, err))
-// headersByNumber returns headers from the given number.
+		}
-func (tc *testChain) headersByNumber(origin uint64, amount int, skip int, reverse bool) []*types.Header {
+		tbc.chain = chain
-	result := make([]*types.Header, 0, amount)
+	})
-
+	return tbc.chain
-	if !reverse {
-		for num := origin; num < uint64(len(tc.chain)) && len(result) < amount; num += uint64(skip) + 1 {
-			if header, ok := tc.headerm[tc.chain[int(num)]]; ok {
-				result = append(result, header)
-			}
-		}
-	} else {
-		for num := int64(origin); num >= 0 && len(result) < amount; num -= int64(skip) + 1 {
-			if header, ok := tc.headerm[tc.chain[int(num)]]; ok {
-				result = append(result, header)
-			}
-		}
-	}
-	return result
-}
-
-// receipts returns the receipts of the given block hashes.
-func (tc *testChain) receipts(hashes []common.Hash) [][]*types.Receipt {
-	results := make([][]*types.Receipt, 0, len(hashes))
-	for _, hash := range hashes {
-		if receipt, ok := tc.receiptm[hash]; ok {
-			results = append(results, receipt)
-		}
-	}
-	return results
-}
-
-// bodies returns the block bodies of the given block hashes.
-func (tc *testChain) bodies(hashes []common.Hash) ([][]*types.Transaction, [][]*types.Header) {
-	transactions := make([][]*types.Transaction, 0, len(hashes))
-	uncles := make([][]*types.Header, 0, len(hashes))
-	for _, hash := range hashes {
-		if block, ok := tc.blockm[hash]; ok {
-			transactions = append(transactions, block.Transactions())
-			uncles = append(uncles, block.Uncles())
-		}
-	}
-	return transactions, uncles
-}
-
-func (tc *testChain) hashToNumber(target common.Hash) (uint64, bool) {
-	for num, hash := range tc.chain {
-		if hash == target {
-			return uint64(num), true
-		}
-	}
-	return 0, false
 }

eth/downloader/types.go

@@ -1,79 +0,0 @@
-// Copyright 2015 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-package downloader
-
-import (
-	"fmt"
-
-	"github.com/ethereum/go-ethereum/core/types"
-)
-
-// peerDropFn is a callback type for dropping a peer detected as malicious.
-type peerDropFn func(id string)
-
-// dataPack is a data message returned by a peer for some query.
-type dataPack interface {
-	PeerId() string
-	Items() int
-	Stats() string
-}
-
-// headerPack is a batch of block headers returned by a peer.
-type headerPack struct {
-	peerID  string
-	headers []*types.Header
-}
-
-func (p *headerPack) PeerId() string { return p.peerID }
-func (p *headerPack) Items() int     { return len(p.headers) }
-func (p *headerPack) Stats() string  { return fmt.Sprintf("%d", len(p.headers)) }
-
-// bodyPack is a batch of block bodies returned by a peer.
-type bodyPack struct {
-	peerID       string
-	transactions [][]*types.Transaction
-	uncles       [][]*types.Header
-}
-
-func (p *bodyPack) PeerId() string { return p.peerID }
-func (p *bodyPack) Items() int {
-	if len(p.transactions) <= len(p.uncles) {
-		return len(p.transactions)
-	}
-	return len(p.uncles)
-}
-func (p *bodyPack) Stats() string { return fmt.Sprintf("%d:%d", len(p.transactions), len(p.uncles)) }
-
-// receiptPack is a batch of receipts returned by a peer.
-type receiptPack struct {
-	peerID   string
-	receipts [][]*types.Receipt
-}
-
-func (p *receiptPack) PeerId() string { return p.peerID }
-func (p *receiptPack) Items() int     { return len(p.receipts) }
-func (p *receiptPack) Stats() string  { return fmt.Sprintf("%d", len(p.receipts)) }
-
-// statePack is a batch of states returned by a peer.
-type statePack struct {
-	peerID string
-	states [][]byte
-}
-
-func (p *statePack) PeerId() string { return p.peerID }
-func (p *statePack) Items() int     { return len(p.states) }
-func (p *statePack) Stats() string  { return fmt.Sprintf("%d", len(p.states)) }

eth/fetcher/block_fetcher.go

@@ -26,6 +26,7 @@ import (
 	"github.com/ethereum/go-ethereum/common/prque"
 	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/eth/protocols/eth"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/metrics"
 	"github.com/ethereum/go-ethereum/trie"
@@ -74,10 +75,10 @@ type HeaderRetrievalFn func(common.Hash) *types.Header
 type blockRetrievalFn func(common.Hash) *types.Block
 
 // headerRequesterFn is a callback type for sending a header retrieval request.
-type headerRequesterFn func(common.Hash) error
+type headerRequesterFn func(common.Hash, chan *eth.Response) (*eth.Request, error)
 
 // bodyRequesterFn is a callback type for sending a body retrieval request.
-type bodyRequesterFn func([]common.Hash) error
+type bodyRequesterFn func([]common.Hash, chan *eth.Response) (*eth.Request, error)
 
 // headerVerifierFn is a callback type to verify a block's header for fast propagation.
 type headerVerifierFn func(header *types.Header) error
@@ -461,15 +462,28 @@ func (f *BlockFetcher) loop() {
 
 				// Create a closure of the fetch and schedule in on a new thread
 				fetchHeader, hashes := f.fetching[hashes[0]].fetchHeader, hashes
-				go func() {
+				go func(peer string) {
 					if f.fetchingHook != nil {
 						f.fetchingHook(hashes)
 					}
 					for _, hash := range hashes {
 						headerFetchMeter.Mark(1)
-						fetchHeader(hash) // Suboptimal, but protocol doesn't allow batch header retrievals
+						go func(hash common.Hash) {
+							resCh := make(chan *eth.Response)
+
+							req, err := fetchHeader(hash, resCh)
+							if err != nil {
+								return // Legacy code, yolo
 							}
-				}()
+							defer req.Close()
+
+							res := <-resCh
+							res.Done <- nil
+
+							f.FilterHeaders(peer, *res.Res.(*eth.BlockHeadersPacket), time.Now().Add(res.Time))
+						}(hash)
+					}
+				}(peer)
 			}
 			// Schedule the next fetch if blocks are still pending
 			f.rescheduleFetch(fetchTimer)
@@ -497,8 +511,24 @@ func (f *BlockFetcher) loop() {
 				if f.completingHook != nil {
 					f.completingHook(hashes)
 				}
+				fetchBodies := f.completing[hashes[0]].fetchBodies
 				bodyFetchMeter.Mark(int64(len(hashes)))
-				go f.completing[hashes[0]].fetchBodies(hashes)
+
+				go func(peer string, hashes []common.Hash) {
+					resCh := make(chan *eth.Response)
+
+					req, err := fetchBodies(hashes, resCh)
+					if err != nil {
+						return // Legacy code, yolo
+					}
+					defer req.Close()
+
+					res := <-resCh
+					res.Done <- nil
+
+					txs, uncles := res.Res.(*eth.BlockBodiesPacket).Unpack()
+					f.FilterBodies(peer, txs, uncles, time.Now())
+				}(peer, hashes)
 			}
 			// Schedule the next fetch if blocks are still pending
 			f.rescheduleComplete(completeTimer)

eth/fetcher/block_fetcher_test.go

@@ -30,6 +30,7 @@ import (
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/eth/protocols/eth"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/trie"
 )
@@ -60,8 +61,8 @@ func makeChain(n int, seed byte, parent *types.Block) ([]common.Hash, map[common
 			block.AddTx(tx)
 		}
 		// If the block number is a multiple of 5, add a bonus uncle to the block
-		if i%5 == 0 {
+		if i > 0 && i%5 == 0 {
-			block.AddUncle(&types.Header{ParentHash: block.PrevBlock(i - 1).Hash(), Number: big.NewInt(int64(i - 1))})
+			block.AddUncle(&types.Header{ParentHash: block.PrevBlock(i - 2).Hash(), Number: big.NewInt(int64(i - 1))})
 		}
 	})
 	hashes := make([]common.Hash, n+1)
@@ -195,16 +196,26 @@ func (f *fetcherTester) makeHeaderFetcher(peer string, blocks map[common.Hash]*t
 		closure[hash] = block
 	}
 	// Create a function that return a header from the closure
-	return func(hash common.Hash) error {
+	return func(hash common.Hash, sink chan *eth.Response) (*eth.Request, error) {
 		// Gather the blocks to return
 		headers := make([]*types.Header, 0, 1)
 		if block, ok := closure[hash]; ok {
 			headers = append(headers, block.Header())
 		}
 		// Return on a new thread
-		go f.fetcher.FilterHeaders(peer, headers, time.Now().Add(drift))
+		req := &eth.Request{
-
+			Peer: peer,
-		return nil
+		}
+		res := &eth.Response{
+			Req:  req,
+			Res:  (*eth.BlockHeadersPacket)(&headers),
+			Time: drift,
+			Done: make(chan error, 1), // Ignore the returned status
+		}
+		go func() {
+			sink <- res
+		}()
+		return req, nil
 	}
 }
 
@@ -215,7 +226,7 @@ func (f *fetcherTester) makeBodyFetcher(peer string, blocks map[common.Hash]*typ
 		closure[hash] = block
 	}
 	// Create a function that returns blocks from the closure
-	return func(hashes []common.Hash) error {
+	return func(hashes []common.Hash, sink chan *eth.Response) (*eth.Request, error) {
 		// Gather the block bodies to return
 		transactions := make([][]*types.Transaction, 0, len(hashes))
 		uncles := make([][]*types.Header, 0, len(hashes))
@@ -227,14 +238,33 @@ func (f *fetcherTester) makeBodyFetcher(peer string, blocks map[common.Hash]*typ
 			}
 		}
 		// Return on a new thread
-		go f.fetcher.FilterBodies(peer, transactions, uncles, time.Now().Add(drift))
+		bodies := make([]*eth.BlockBody, len(transactions))
-
+		for i, txs := range transactions {
-		return nil
+			bodies[i] = &eth.BlockBody{
+				Transactions: txs,
+				Uncles:       uncles[i],
+			}
+		}
+		req := &eth.Request{
+			Peer: peer,
+		}
+		res := &eth.Response{
+			Req:  req,
+			Res:  (*eth.BlockBodiesPacket)(&bodies),
+			Time: drift,
+			Done: make(chan error, 1), // Ignore the returned status
+		}
+		go func() {
+			sink <- res
+		}()
+		return req, nil
 	}
 }
 
 // verifyFetchingEvent verifies that one single event arrive on a fetching channel.
 func verifyFetchingEvent(t *testing.T, fetching chan []common.Hash, arrive bool) {
+	t.Helper()
+
 	if arrive {
 		select {
 		case <-fetching:
@@ -252,6 +282,8 @@ func verifyFetchingEvent(t *testing.T, fetching chan []common.Hash, arrive bool)
 
 // verifyCompletingEvent verifies that one single event arrive on an completing channel.
 func verifyCompletingEvent(t *testing.T, completing chan []common.Hash, arrive bool) {
+	t.Helper()
+
 	if arrive {
 		select {
 		case <-completing:
@@ -269,6 +301,8 @@ func verifyCompletingEvent(t *testing.T, completing chan []common.Hash, arrive b
 
 // verifyImportEvent verifies that one single event arrive on an import channel.
 func verifyImportEvent(t *testing.T, imported chan interface{}, arrive bool) {
+	t.Helper()
+
 	if arrive {
 		select {
 		case <-imported:
@@ -287,6 +321,8 @@ func verifyImportEvent(t *testing.T, imported chan interface{}, arrive bool) {
 // verifyImportCount verifies that exactly count number of events arrive on an
 // import hook channel.
 func verifyImportCount(t *testing.T, imported chan interface{}, count int) {
+	t.Helper()
+
 	for i := 0; i < count; i++ {
 		select {
 		case <-imported:
@@ -299,6 +335,8 @@ func verifyImportCount(t *testing.T, imported chan interface{}, count int) {
 
 // verifyImportDone verifies that no more events are arriving on an import channel.
 func verifyImportDone(t *testing.T, imported chan interface{}) {
+	t.Helper()
+
 	select {
 	case <-imported:
 		t.Fatalf("extra block imported")
@@ -308,6 +346,8 @@ func verifyImportDone(t *testing.T, imported chan interface{}) {
 
 // verifyChainHeight verifies the chain height is as expected.
 func verifyChainHeight(t *testing.T, fetcher *fetcherTester, height uint64) {
+	t.Helper()
+
 	if fetcher.chainHeight() != height {
 		t.Fatalf("chain height mismatch, got %d, want %d", fetcher.chainHeight(), height)
 	}
@@ -368,13 +408,13 @@ func testConcurrentAnnouncements(t *testing.T, light bool) {
 	secondBodyFetcher := tester.makeBodyFetcher("second", blocks, 0)
 
 	counter := uint32(0)
-	firstHeaderWrapper := func(hash common.Hash) error {
+	firstHeaderWrapper := func(hash common.Hash, sink chan *eth.Response) (*eth.Request, error) {
 		atomic.AddUint32(&counter, 1)
-		return firstHeaderFetcher(hash)
+		return firstHeaderFetcher(hash, sink)
 	}
-	secondHeaderWrapper := func(hash common.Hash) error {
+	secondHeaderWrapper := func(hash common.Hash, sink chan *eth.Response) (*eth.Request, error) {
 		atomic.AddUint32(&counter, 1)
-		return secondHeaderFetcher(hash)
+		return secondHeaderFetcher(hash, sink)
 	}
 	// Iteratively announce blocks until all are imported
 	imported := make(chan interface{})
@@ -468,15 +508,20 @@ func testPendingDeduplication(t *testing.T, light bool) {
 
 	delay := 50 * time.Millisecond
 	counter := uint32(0)
-	headerWrapper := func(hash common.Hash) error {
+	headerWrapper := func(hash common.Hash, sink chan *eth.Response) (*eth.Request, error) {
 		atomic.AddUint32(&counter, 1)
 
 		// Simulate a long running fetch
+		resink := make(chan *eth.Response)
+		req, err := headerFetcher(hash, resink)
+		if err == nil {
 			go func() {
+				res := <-resink
 				time.Sleep(delay)
-			headerFetcher(hash)
+				sink <- res
 			}()
-		return nil
+		}
+		return req, err
 	}
 	checkNonExist := func() bool {
 		return tester.getBlock(hashes[0]) == nil

eth/handler.go

@@ -83,8 +83,8 @@ type handlerConfig struct {
 	TxPool     txPool                    // Transaction pool to propagate from
 	Merger     *consensus.Merger         // The manager for eth1/2 transition
 	Network    uint64                    // Network identifier to adfvertise
-	Sync       downloader.SyncMode       // Whether to fast or full sync
+	Sync       downloader.SyncMode       // Whether to snap or full sync
-	BloomCache uint64                    // Megabytes to alloc for fast sync bloom
+	BloomCache uint64                    // Megabytes to alloc for snap sync bloom
 	EventMux   *event.TypeMux            // Legacy event mux, deprecate for `feed`
 	Checkpoint *params.TrustedCheckpoint // Hard coded checkpoint for sync challenges
 	Whitelist  map[uint64]common.Hash    // Hard coded whitelist for sync challenged
@@ -94,8 +94,7 @@ type handler struct {
 	networkID  uint64
 	forkFilter forkid.Filter // Fork ID filter, constant across the lifetime of the node
 
-	fastSync  uint32 // Flag whether fast sync is enabled (gets disabled if we already have blocks)
+	snapSync  uint32 // Flag whether snap sync is enabled (gets disabled if we already have blocks)
-	snapSync  uint32 // Flag whether fast sync should operate on top of the snap protocol
 	acceptTxs uint32 // Flag whether we're considered synchronised (enables transaction processing)
 
 	checkpointNumber uint64      // Block number for the sync progress validator to cross reference
@@ -147,44 +146,41 @@ func newHandler(config *handlerConfig) (*handler, error) {
 		quitSync:   make(chan struct{}),
 	}
 	if config.Sync == downloader.FullSync {
-		// The database seems empty as the current block is the genesis. Yet the fast
+		// The database seems empty as the current block is the genesis. Yet the snap
-		// block is ahead, so fast sync was enabled for this node at a certain point.
+		// block is ahead, so snap sync was enabled for this node at a certain point.
 		// The scenarios where this can happen is
-		// * if the user manually (or via a bad block) rolled back a fast sync node
+		// * if the user manually (or via a bad block) rolled back a snap sync node
 		//   below the sync point.
-		// * the last fast sync is not finished while user specifies a full sync this
+		// * the last snap sync is not finished while user specifies a full sync this
 		//   time. But we don't have any recent state for full sync.
-		// In these cases however it's safe to reenable fast sync.
+		// In these cases however it's safe to reenable snap sync.
 		fullBlock, fastBlock := h.chain.CurrentBlock(), h.chain.CurrentFastBlock()
 		if fullBlock.NumberU64() == 0 && fastBlock.NumberU64() > 0 {
-			h.fastSync = uint32(1)
+			h.snapSync = uint32(1)
-			log.Warn("Switch sync mode from full sync to fast sync")
+			log.Warn("Switch sync mode from full sync to snap sync")
 		}
 	} else {
 		if h.chain.CurrentBlock().NumberU64() > 0 {
-			// Print warning log if database is not empty to run fast sync.
+			// Print warning log if database is not empty to run snap sync.
-			log.Warn("Switch sync mode from fast sync to full sync")
+			log.Warn("Switch sync mode from snap sync to full sync")
 		} else {
-			// If fast sync was requested and our database is empty, grant it
+			// If snap sync was requested and our database is empty, grant it
-			h.fastSync = uint32(1)
-			if config.Sync == downloader.SnapSync {
 			h.snapSync = uint32(1)
 		}
 	}
-	}
 	// If we have trusted checkpoints, enforce them on the chain
 	if config.Checkpoint != nil {
 		h.checkpointNumber = (config.Checkpoint.SectionIndex+1)*params.CHTFrequency - 1
 		h.checkpointHash = config.Checkpoint.SectionHead
 	}
-	// Construct the downloader (long sync) and its backing state bloom if fast
+	// Construct the downloader (long sync) and its backing state bloom if snap
 	// sync is requested. The downloader is responsible for deallocating the state
 	// bloom when it's done.
 	// Note: we don't enable it if snap-sync is performed, since it's very heavy
-	// and the heal-portion of the snap sync is much lighter than fast. What we particularly
+	// and the heal-portion of the snap sync is much lighter than snap. What we particularly
 	// want to avoid, is a 90%-finished (but restarted) snap-sync to begin
 	// indexing the entire trie
-	if atomic.LoadUint32(&h.fastSync) == 1 && atomic.LoadUint32(&h.snapSync) == 0 {
+	if atomic.LoadUint32(&h.snapSync) == 1 && atomic.LoadUint32(&h.snapSync) == 0 {
 		h.stateBloom = trie.NewSyncBloom(config.BloomCache, config.Database)
 	}
 	h.downloader = downloader.New(h.checkpointNumber, config.Database, h.stateBloom, h.eventMux, h.chain, nil, h.removePeer)
@@ -236,12 +232,12 @@ func newHandler(config *handlerConfig) (*handler, error) {
 			log.Warn("Unsynced yet, discarded propagated block", "number", blocks[0].Number(), "hash", blocks[0].Hash())
 			return 0, nil
 		}
-		// If fast sync is running, deny importing weird blocks. This is a problematic
+		// If snap sync is running, deny importing weird blocks. This is a problematic
-		// clause when starting up a new network, because fast-syncing miners might not
+		// clause when starting up a new network, because snap-syncing miners might not
 		// accept each others' blocks until a restart. Unfortunately we haven't figured
 		// out a way yet where nodes can decide unilaterally whether the network is new
 		// or not. This should be fixed if we figure out a solution.
-		if atomic.LoadUint32(&h.fastSync) == 1 {
+		if atomic.LoadUint32(&h.snapSync) == 1 {
 			log.Warn("Fast syncing, discarded propagated block", "number", blocks[0].Number(), "hash", blocks[0].Hash())
 			return 0, nil
 		}
@@ -365,30 +361,93 @@ func (h *handler) runEthPeer(peer *eth.Peer, handler eth.Handler) error {
 	// after this will be sent via broadcasts.
 	h.syncTransactions(peer)
 
+	// Create a notification channel for pending requests if the peer goes down
+	dead := make(chan struct{})
+	defer close(dead)
+
 	// If we have a trusted CHT, reject all peers below that (avoid fast sync eclipse)
 	if h.checkpointHash != (common.Hash{}) {
 		// Request the peer's checkpoint header for chain height/weight validation
-		if err := peer.RequestHeadersByNumber(h.checkpointNumber, 1, 0, false); err != nil {
+		resCh := make(chan *eth.Response)
+		if _, err := peer.RequestHeadersByNumber(h.checkpointNumber, 1, 0, false, resCh); err != nil {
 			return err
 		}
 		// Start a timer to disconnect if the peer doesn't reply in time
-		p.syncDrop = time.AfterFunc(syncChallengeTimeout, func() {
+		go func() {
+			timeout := time.NewTimer(syncChallengeTimeout)
+			defer timeout.Stop()
+
+			select {
+			case res := <-resCh:
+				headers := ([]*types.Header)(*res.Res.(*eth.BlockHeadersPacket))
+				if len(headers) == 0 {
+					// If we're doing a snap sync, we must enforce the checkpoint
+					// block to avoid eclipse attacks. Unsynced nodes are welcome
+					// to connect after we're done joining the network.
+					if atomic.LoadUint32(&h.snapSync) == 1 {
+						peer.Log().Warn("Dropping unsynced node during sync", "addr", peer.RemoteAddr(), "type", peer.Name())
+						res.Done <- errors.New("unsynced node cannot serve sync")
+						return
+					}
+					res.Done <- nil
+					return
+				}
+				// Validate the header and either drop the peer or continue
+				if len(headers) > 1 {
+					res.Done <- errors.New("too many headers in checkpoint response")
+					return
+				}
+				if headers[0].Hash() != h.checkpointHash {
+					res.Done <- errors.New("checkpoint hash mismatch")
+					return
+				}
+				res.Done <- nil
+
+			case <-timeout.C:
 				peer.Log().Warn("Checkpoint challenge timed out, dropping", "addr", peer.RemoteAddr(), "type", peer.Name())
 				h.removePeer(peer.ID())
-		})
+
-		// Make sure it's cleaned up if the peer dies off
+			case <-dead:
-		defer func() {
+				// Peer handler terminated, abort all goroutines
-			if p.syncDrop != nil {
-				p.syncDrop.Stop()
-				p.syncDrop = nil
 			}
 		}()
 	}
 	// If we have any explicit whitelist block hashes, request them
-	for number := range h.whitelist {
+	for number, hash := range h.whitelist {
-		if err := peer.RequestHeadersByNumber(number, 1, 0, false); err != nil {
+		resCh := make(chan *eth.Response)
+		if _, err := peer.RequestHeadersByNumber(number, 1, 0, false, resCh); err != nil {
 			return err
 		}
+		go func(number uint64, hash common.Hash) {
+			timeout := time.NewTimer(syncChallengeTimeout)
+			defer timeout.Stop()
+
+			select {
+			case res := <-resCh:
+				headers := ([]*types.Header)(*res.Res.(*eth.BlockHeadersPacket))
+				if len(headers) == 0 {
+					// Whitelisted blocks are allowed to be missing if the remote
+					// node is not yet synced
+					res.Done <- nil
+					return
+				}
+				// Validate the header and either drop the peer or continue
+				if len(headers) > 1 {
+					res.Done <- errors.New("too many headers in whitelist response")
+					return
+				}
+				if headers[0].Number.Uint64() != number || headers[0].Hash() != hash {
+					peer.Log().Info("Whitelist mismatch, dropping peer", "number", number, "hash", headers[0].Hash(), "want", hash)
+					res.Done <- errors.New("whitelist block mismatch")
+					return
+				}
+				peer.Log().Debug("Whitelist block verified", "number", number, "hash", hash)
+
+			case <-timeout.C:
+				peer.Log().Warn("Whitelist challenge timed out, dropping", "addr", peer.RemoteAddr(), "type", peer.Name())
+				h.removePeer(peer.ID())
+			}
+		}(number, hash)
 	}
 	// Handle incoming messages until the connection is torn down
 	return handler(peer)

eth/handler_eth.go

@@ -17,7 +17,6 @@
 package eth
 
 import (
-	"errors"
 	"fmt"
 	"math/big"
 	"sync/atomic"
@@ -27,7 +26,6 @@ import (
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/eth/protocols/eth"
-	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/trie"
 )
@@ -64,25 +62,6 @@ func (h *ethHandler) AcceptTxs() bool {
 func (h *ethHandler) Handle(peer *eth.Peer, packet eth.Packet) error {
 	// Consume any broadcasts and announces, forwarding the rest to the downloader
 	switch packet := packet.(type) {
-	case *eth.BlockHeadersPacket:
-		return h.handleHeaders(peer, *packet)
-
-	case *eth.BlockBodiesPacket:
-		txset, uncleset := packet.Unpack()
-		return h.handleBodies(peer, txset, uncleset)
-
-	case *eth.NodeDataPacket:
-		if err := h.downloader.DeliverNodeData(peer.ID(), *packet); err != nil {
-			log.Debug("Failed to deliver node state data", "err", err)
-		}
-		return nil
-
-	case *eth.ReceiptsPacket:
-		if err := h.downloader.DeliverReceipts(peer.ID(), *packet); err != nil {
-			log.Debug("Failed to deliver receipts", "err", err)
-		}
-		return nil
-
 	case *eth.NewBlockHashesPacket:
 		hashes, numbers := packet.Unpack()
 		return h.handleBlockAnnounces(peer, hashes, numbers)
@@ -104,79 +83,6 @@ func (h *ethHandler) Handle(peer *eth.Peer, packet eth.Packet) error {
 	}
 }
 
-// handleHeaders is invoked from a peer's message handler when it transmits a batch
-// of headers for the local node to process.
-func (h *ethHandler) handleHeaders(peer *eth.Peer, headers []*types.Header) error {
-	p := h.peers.peer(peer.ID())
-	if p == nil {
-		return errors.New("unregistered during callback")
-	}
-	// If no headers were received, but we're expencting a checkpoint header, consider it that
-	if len(headers) == 0 && p.syncDrop != nil {
-		// Stop the timer either way, decide later to drop or not
-		p.syncDrop.Stop()
-		p.syncDrop = nil
-
-		// If we're doing a fast (or snap) sync, we must enforce the checkpoint block to avoid
-		// eclipse attacks. Unsynced nodes are welcome to connect after we're done
-		// joining the network
-		if atomic.LoadUint32(&h.fastSync) == 1 {
-			peer.Log().Warn("Dropping unsynced node during sync", "addr", peer.RemoteAddr(), "type", peer.Name())
-			return errors.New("unsynced node cannot serve sync")
-		}
-	}
-	// Filter out any explicitly requested headers, deliver the rest to the downloader
-	filter := len(headers) == 1
-	if filter {
-		// If it's a potential sync progress check, validate the content and advertised chain weight
-		if p.syncDrop != nil && headers[0].Number.Uint64() == h.checkpointNumber {
-			// Disable the sync drop timer
-			p.syncDrop.Stop()
-			p.syncDrop = nil
-
-			// Validate the header and either drop the peer or continue
-			if headers[0].Hash() != h.checkpointHash {
-				return errors.New("checkpoint hash mismatch")
-			}
-			return nil
-		}
-		// Otherwise if it's a whitelisted block, validate against the set
-		if want, ok := h.whitelist[headers[0].Number.Uint64()]; ok {
-			if hash := headers[0].Hash(); want != hash {
-				peer.Log().Info("Whitelist mismatch, dropping peer", "number", headers[0].Number.Uint64(), "hash", hash, "want", want)
-				return errors.New("whitelist block mismatch")
-			}
-			peer.Log().Debug("Whitelist block verified", "number", headers[0].Number.Uint64(), "hash", want)
-		}
-		// Irrelevant of the fork checks, send the header to the fetcher just in case
-		headers = h.blockFetcher.FilterHeaders(peer.ID(), headers, time.Now())
-	}
-	if len(headers) > 0 || !filter {
-		err := h.downloader.DeliverHeaders(peer.ID(), headers)
-		if err != nil {
-			log.Debug("Failed to deliver headers", "err", err)
-		}
-	}
-	return nil
-}
-
-// handleBodies is invoked from a peer's message handler when it transmits a batch
-// of block bodies for the local node to process.
-func (h *ethHandler) handleBodies(peer *eth.Peer, txs [][]*types.Transaction, uncles [][]*types.Header) error {
-	// Filter out any explicitly requested bodies, deliver the rest to the downloader
-	filter := len(txs) > 0 || len(uncles) > 0
-	if filter {
-		txs, uncles = h.blockFetcher.FilterBodies(peer.ID(), txs, uncles, time.Now())
-	}
-	if len(txs) > 0 || len(uncles) > 0 || !filter {
-		err := h.downloader.DeliverBodies(peer.ID(), txs, uncles)
-		if err != nil {
-			log.Debug("Failed to deliver bodies", "err", err)
-		}
-	}
-	return nil
-}
-
 // handleBlockAnnounces is invoked from a peer's message handler when it transmits a
 // batch of block announcements for the local node to process.
 func (h *ethHandler) handleBlockAnnounces(peer *eth.Peer, hashes []common.Hash, numbers []uint64) error {

eth/handler_eth_test.go

@@ -354,7 +354,7 @@ func testSendTransactions(t *testing.T, protocol uint) {
 	seen := make(map[common.Hash]struct{})
 	for len(seen) < len(insert) {
 		switch protocol {
-		case 65, 66:
+		case 66:
 			select {
 			case hashes := <-anns:
 				for _, hash := range hashes {
@@ -364,7 +364,7 @@ func testSendTransactions(t *testing.T, protocol uint) {
 					seen[hash] = struct{}{}
 				}
 			case <-bcasts:
-				t.Errorf("initial tx broadcast received on post eth/65")
+				t.Errorf("initial tx broadcast received on post eth/66")
 			}
 
 		default:
@@ -389,6 +389,7 @@ func testTransactionPropagation(t *testing.T, protocol uint) {
 	// to receive them. We need multiple sinks since a one-to-one peering would
 	// broadcast all transactions without announcement.
 	source := newTestHandler()
+	source.handler.snapSync = 0 // Avoid requiring snap, otherwise some will be dropped below
 	defer source.close()
 
 	sinks := make([]*testHandler, 10)
@@ -406,7 +407,7 @@ func testTransactionPropagation(t *testing.T, protocol uint) {
 		defer sourcePipe.Close()
 		defer sinkPipe.Close()
 
-		sourcePeer := eth.NewPeer(protocol, p2p.NewPeerPipe(enode.ID{byte(i)}, "", nil, sourcePipe), sourcePipe, source.txpool)
+		sourcePeer := eth.NewPeer(protocol, p2p.NewPeerPipe(enode.ID{byte(i + 1)}, "", nil, sourcePipe), sourcePipe, source.txpool)
 		sinkPeer := eth.NewPeer(protocol, p2p.NewPeerPipe(enode.ID{0}, "", nil, sinkPipe), sinkPipe, sink.txpool)
 		defer sourcePeer.Close()
 		defer sinkPeer.Close()
@@ -438,12 +439,13 @@ func testTransactionPropagation(t *testing.T, protocol uint) {
 
 	// Iterate through all the sinks and ensure they all got the transactions
 	for i := range sinks {
-		for arrived := 0; arrived < len(txs); {
+		for arrived, timeout := 0, false; arrived < len(txs) && !timeout; {
 			select {
 			case event := <-txChs[i]:
 				arrived += len(event.Txs)
-			case <-time.NewTimer(time.Second).C:
+			case <-time.After(time.Second):
 				t.Errorf("sink %d: transaction propagation timed out: have %d, want %d", i, arrived, len(txs))
+				timeout = true
 			}
 		}
 	}
@@ -463,23 +465,23 @@ func TestCheckpointChallenge(t *testing.T) {
 	}{
 		// If checkpointing is not enabled locally, don't challenge and don't drop
 		{downloader.FullSync, false, false, false, false, false},
-		{downloader.FastSync, false, false, false, false, false},
+		{downloader.SnapSync, false, false, false, false, false},
 
 		// If checkpointing is enabled locally and remote response is empty, only drop during fast sync
 		{downloader.FullSync, true, false, true, false, false},
-		{downloader.FastSync, true, false, true, false, true}, // Special case, fast sync, unsynced peer
+		{downloader.SnapSync, true, false, true, false, true}, // Special case, fast sync, unsynced peer
 
 		// If checkpointing is enabled locally and remote response mismatches, always drop
 		{downloader.FullSync, true, false, false, false, true},
-		{downloader.FastSync, true, false, false, false, true},
+		{downloader.SnapSync, true, false, false, false, true},
 
 		// If checkpointing is enabled locally and remote response matches, never drop
 		{downloader.FullSync, true, false, false, true, false},
-		{downloader.FastSync, true, false, false, true, false},
+		{downloader.SnapSync, true, false, false, true, false},
 
 		// If checkpointing is enabled locally and remote times out, always drop
 		{downloader.FullSync, true, true, false, true, true},
-		{downloader.FastSync, true, true, false, true, true},
+		{downloader.SnapSync, true, true, false, true, true},
 	}
 	for _, tt := range tests {
 		t.Run(fmt.Sprintf("sync %v checkpoint %v timeout %v empty %v match %v", tt.syncmode, tt.checkpoint, tt.timeout, tt.empty, tt.match), func(t *testing.T) {
@@ -500,10 +502,10 @@ func testCheckpointChallenge(t *testing.T, syncmode downloader.SyncMode, checkpo
 	handler := newTestHandler()
 	defer handler.close()
 
-	if syncmode == downloader.FastSync {
+	if syncmode == downloader.SnapSync {
-		atomic.StoreUint32(&handler.handler.fastSync, 1)
+		atomic.StoreUint32(&handler.handler.snapSync, 1)
 	} else {
-		atomic.StoreUint32(&handler.handler.fastSync, 0)
+		atomic.StoreUint32(&handler.handler.snapSync, 0)
 	}
 	var response *types.Header
 	if checkpoint {

eth/handler_test.go

@@ -152,7 +152,7 @@ func newTestHandlerWithBlocks(blocks int) *testHandler {
 		TxPool:     txpool,
 		Merger:     consensus.NewMerger(rawdb.NewMemoryDatabase()),
 		Network:    1,
-		Sync:       downloader.FastSync,
+		Sync:       downloader.SnapSync,
 		BloomCache: 1,
 	})
 	handler.Start(1000)

eth/peer.go

@@ -18,8 +18,6 @@ package eth
 
 import (
 	"math/big"
-	"sync"
-	"time"
 
 	"github.com/ethereum/go-ethereum/eth/protocols/eth"
 	"github.com/ethereum/go-ethereum/eth/protocols/snap"
@@ -37,10 +35,7 @@ type ethPeerInfo struct {
 type ethPeer struct {
 	*eth.Peer
 	snapExt  *snapPeer     // Satellite `snap` connection
-
-	syncDrop *time.Timer   // Connection dropper if `eth` sync progress isn't validated in time
 	snapWait chan struct{} // Notification channel for snap connections
-	lock     sync.RWMutex  // Mutex protecting the internal fields
 }
 
 // info gathers and returns some `eth` protocol metadata known about a peer.

eth/protocols/eth/dispatcher.go

@@ -0,0 +1,247 @@
+// Copyright 2021 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package eth
+
+import (
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/ethereum/go-ethereum/p2p"
+)
+
+var (
+	// errDisconnected is returned if a request is attempted to be made to a peer
+	// that was already closed.
+	errDisconnected = errors.New("disconnected")
+
+	// errDanglingResponse is returned if a response arrives with a request id
+	// which does not match to any existing pending requests.
+	errDanglingResponse = errors.New("response to non-existent request")
+
+	// errMismatchingResponseType is returned if the remote peer sent a different
+	// packet type as a response to a request than what the local node expected.
+	errMismatchingResponseType = errors.New("mismatching response type")
+)
+
+// Request is a pending request to allow tracking it and delivering a response
+// back to the requester on their chosen channel.
+type Request struct {
+	peer *Peer  // Peer to which this request belogs for untracking
+	id   uint64 // Request ID to match up replies to
+
+	sink   chan *Response // Channel to deliver the response on
+	cancel chan struct{}  // Channel to cancel requests ahead of time
+
+	code uint64      // Message code of the request packet
+	want uint64      // Message code of the response packet
+	data interface{} // Data content of the request packet
+
+	Peer string    // Demultiplexer if cross-peer requests are batched together
+	Sent time.Time // Timestamp when the request was sent
+}
+
+// Close aborts an in-flight request. Although there's no way to notify the
+// remote peer about the cancellation, this method notifies the dispatcher to
+// discard any late responses.
+func (r *Request) Close() error {
+	if r.peer == nil { // Tests mock out the dispatcher, skip internal cancellation
+		return nil
+	}
+	cancelOp := &cancel{
+		id:   r.id,
+		fail: make(chan error),
+	}
+	select {
+	case r.peer.reqCancel <- cancelOp:
+		if err := <-cancelOp.fail; err != nil {
+			return err
+		}
+		close(r.cancel)
+		return nil
+	case <-r.peer.term:
+		return errDisconnected
+	}
+}
+
+// request is a wrapper around a client Request that has an error channel to
+// signal on if sending the request already failed on a network level.
+type request struct {
+	req  *Request
+	fail chan error
+}
+
+// cancel is a maintenance type on the dispatcher to stop tracking a pending
+// request.
+type cancel struct {
+	id   uint64 // Request ID to stop tracking
+	fail chan error
+}
+
+// Response is a reply packet to a previously created request. It is delivered
+// on the channel assigned by the requester subsystem and contains the original
+// request embedded to allow uniquely matching it caller side.
+type Response struct {
+	id   uint64    // Request ID to match up this reply to
+	recv time.Time // Timestamp when the request was received
+	code uint64    // Response packet type to cross validate with request
+
+	Req  *Request      // Original request to cross-reference with
+	Res  interface{}   // Remote response for the request query
+	Time time.Duration // Time it took for the request to be served
+	Done chan error    // Channel to signal message handling to the reader
+}
+
+// response is a wrapper around a remote Response that has an error channel to
+// signal on if processing the response failed.
+type response struct {
+	res  *Response
+	fail chan error
+}
+
+// dispatchRequest schedules the request to the dispatcher for tracking and
+// network serialization, blocking until it's successfully sent.
+//
+// The returned Request must either be closed before discarding it, or the reply
+// must be waited for and the Response's Done channel signalled.
+func (p *Peer) dispatchRequest(req *Request) error {
+	reqOp := &request{
+		req:  req,
+		fail: make(chan error),
+	}
+	req.cancel = make(chan struct{})
+	req.peer = p
+	req.Peer = p.id
+
+	select {
+	case p.reqDispatch <- reqOp:
+		return <-reqOp.fail
+	case <-p.term:
+		return errDisconnected
+	}
+}
+
+// dispatchRequest fulfils a pending request and delivers it to the requested
+// sink.
+func (p *Peer) dispatchResponse(res *Response) error {
+	resOp := &response{
+		res:  res,
+		fail: make(chan error),
+	}
+	res.recv = time.Now()
+	res.Done = make(chan error)
+
+	select {
+	case p.resDispatch <- resOp:
+		// Ensure the response is accepted by the dispatcher
+		if err := <-resOp.fail; err != nil {
+			return nil
+		}
+		// Deliver the filled out response and wait until it's handled. This
+		// path is a bit funky as Go's select has no order, so if a response
+		// arrives to an already cancelled request, there's a 50-50% changes
+		// of picking on channel or the other. To avoid such cases delivering
+		// the packet upstream, check for cancellation first and only after
+		// block on delivery.
+		select {
+		case <-res.Req.cancel:
+			return nil // Request cancelled, silently discard response
+		default:
+			// Request not yet cancelled, attempt to deliver it, but do watch
+			// for fresh cancellations too
+			select {
+			case res.Req.sink <- res:
+				return <-res.Done // Response delivered, return any errors
+			case <-res.Req.cancel:
+				return nil // Request cancelled, silently discard response
+			}
+		}
+
+	case <-p.term:
+		return errDisconnected
+	}
+}
+
+// dispatcher is a loop that accepts requests from higher layer packages, pushes
+// it to the network and tracks and dispatches the responses back to the original
+// requester.
+func (p *Peer) dispatcher() {
+	pending := make(map[uint64]*Request)
+
+	for {
+		select {
+		case reqOp := <-p.reqDispatch:
+			req := reqOp.req
+			req.Sent = time.Now()
+
+			requestTracker.Track(p.id, p.version, req.code, req.want, req.id)
+			err := p2p.Send(p.rw, req.code, req.data)
+			reqOp.fail <- err
+
+			if err == nil {
+				pending[req.id] = req
+			}
+
+		case cancelOp := <-p.reqCancel:
+			// Retrieve the pendign request to cancel and short circuit if it
+			// has already been serviced and is not available anymore
+			req := pending[cancelOp.id]
+			if req == nil {
+				cancelOp.fail <- nil
+				continue
+			}
+			// Stop tracking the request
+			delete(pending, cancelOp.id)
+			cancelOp.fail <- nil
+
+		case resOp := <-p.resDispatch:
+			res := resOp.res
+			res.Req = pending[res.id]
+
+			// Independent if the request exists or not, track this packet
+			requestTracker.Fulfil(p.id, p.version, res.code, res.id)
+
+			switch {
+			case res.Req == nil:
+				// Response arrived with an untracked ID. Since even cancelled
+				// requests are tracked until fulfilment, a dangling repsponse
+				// means the remote peer implements the protocol badly.
+				resOp.fail <- errDanglingResponse
+
+			case res.Req.want != res.code:
+				// Response arrived, but it's a different packet type than the
+				// one expected by the requester. Either the local code is bad,
+				// or the remote peer send junk. In neither cases can we handle
+				// the packet.
+				resOp.fail <- fmt.Errorf("%w: have %d, want %d", errMismatchingResponseType, res.code, res.Req.want)
+
+			default:
+				// All dispatcher checks passed and the response was initialized
+				// with the matching request. Signal to the delivery routine that
+				// it can wait for a handler response and dispatch the data.
+				res.Time = res.recv.Sub(res.Req.Sent)
+				resOp.fail <- nil
+
+				// Stop tracking the request, the response dispatcher will deliver
+				delete(pending, res.id)
+			}
+
+		case <-p.term:
+			return
+		}
+	}
+}

eth/protocols/eth/handlers.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/rlp"
@@ -34,11 +35,13 @@ func handleGetBlockHeaders66(backend Backend, msg Decoder, peer *Peer) error {
 	if err := msg.Decode(&query); err != nil {
 		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
 	}
-	response := answerGetBlockHeadersQuery(backend, query.GetBlockHeadersPacket, peer)
+	response := ServiceGetBlockHeadersQuery(backend.Chain(), query.GetBlockHeadersPacket, peer)
 	return peer.ReplyBlockHeaders(query.RequestId, response)
 }
 
-func answerGetBlockHeadersQuery(backend Backend, query *GetBlockHeadersPacket, peer *Peer) []*types.Header {
+// ServiceGetBlockHeadersQuery assembles the response to a header query. It is
+// exposed to allow external packages to test protocol behavior.
+func ServiceGetBlockHeadersQuery(chain *core.BlockChain, query *GetBlockHeadersPacket, peer *Peer) []*types.Header {
 	hashMode := query.Origin.Hash != (common.Hash{})
 	first := true
 	maxNonCanonical := uint64(100)
@@ -58,15 +61,15 @@ func answerGetBlockHeadersQuery(backend Backend, query *GetBlockHeadersPacket, p
 		if hashMode {
 			if first {
 				first = false
-				origin = backend.Chain().GetHeaderByHash(query.Origin.Hash)
+				origin = chain.GetHeaderByHash(query.Origin.Hash)
 				if origin != nil {
 					query.Origin.Number = origin.Number.Uint64()
 				}
 			} else {
-				origin = backend.Chain().GetHeader(query.Origin.Hash, query.Origin.Number)
+				origin = chain.GetHeader(query.Origin.Hash, query.Origin.Number)
 			}
 		} else {
-			origin = backend.Chain().GetHeaderByNumber(query.Origin.Number)
+			origin = chain.GetHeaderByNumber(query.Origin.Number)
 		}
 		if origin == nil {
 			break
@@ -82,7 +85,7 @@ func answerGetBlockHeadersQuery(backend Backend, query *GetBlockHeadersPacket, p
 			if ancestor == 0 {
 				unknown = true
 			} else {
-				query.Origin.Hash, query.Origin.Number = backend.Chain().GetAncestor(query.Origin.Hash, query.Origin.Number, ancestor, &maxNonCanonical)
+				query.Origin.Hash, query.Origin.Number = chain.GetAncestor(query.Origin.Hash, query.Origin.Number, ancestor, &maxNonCanonical)
 				unknown = (query.Origin.Hash == common.Hash{})
 			}
 		case hashMode && !query.Reverse:
@@ -96,9 +99,9 @@ func answerGetBlockHeadersQuery(backend Backend, query *GetBlockHeadersPacket, p
 				peer.Log().Warn("GetBlockHeaders skip overflow attack", "current", current, "skip", query.Skip, "next", next, "attacker", infos)
 				unknown = true
 			} else {
-				if header := backend.Chain().GetHeaderByNumber(next); header != nil {
+				if header := chain.GetHeaderByNumber(next); header != nil {
 					nextHash := header.Hash()
-					expOldHash, _ := backend.Chain().GetAncestor(nextHash, next, query.Skip+1, &maxNonCanonical)
+					expOldHash, _ := chain.GetAncestor(nextHash, next, query.Skip+1, &maxNonCanonical)
 					if expOldHash == query.Origin.Hash {
 						query.Origin.Hash, query.Origin.Number = nextHash, next
 					} else {
@@ -130,11 +133,13 @@ func handleGetBlockBodies66(backend Backend, msg Decoder, peer *Peer) error {
 	if err := msg.Decode(&query); err != nil {
 		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
 	}
-	response := answerGetBlockBodiesQuery(backend, query.GetBlockBodiesPacket, peer)
+	response := ServiceGetBlockBodiesQuery(backend.Chain(), query.GetBlockBodiesPacket)
 	return peer.ReplyBlockBodiesRLP(query.RequestId, response)
 }
 
-func answerGetBlockBodiesQuery(backend Backend, query GetBlockBodiesPacket, peer *Peer) []rlp.RawValue {
+// ServiceGetBlockBodiesQuery assembles the response to a body query. It is
+// exposed to allow external packages to test protocol behavior.
+func ServiceGetBlockBodiesQuery(chain *core.BlockChain, query GetBlockBodiesPacket) []rlp.RawValue {
 	// Gather blocks until the fetch or network limits is reached
 	var (
 		bytes  int
@@ -145,7 +150,7 @@ func answerGetBlockBodiesQuery(backend Backend, query GetBlockBodiesPacket, peer
 			lookups >= 2*maxBodiesServe {
 			break
 		}
-		if data := backend.Chain().GetBodyRLP(hash); len(data) != 0 {
+		if data := chain.GetBodyRLP(hash); len(data) != 0 {
 			bodies = append(bodies, data)
 			bytes += len(data)
 		}
@@ -159,11 +164,13 @@ func handleGetNodeData66(backend Backend, msg Decoder, peer *Peer) error {
 	if err := msg.Decode(&query); err != nil {
 		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
 	}
-	response := answerGetNodeDataQuery(backend, query.GetNodeDataPacket, peer)
+	response := ServiceGetNodeDataQuery(backend.Chain(), backend.StateBloom(), query.GetNodeDataPacket)
 	return peer.ReplyNodeData(query.RequestId, response)
 }
 
-func answerGetNodeDataQuery(backend Backend, query GetNodeDataPacket, peer *Peer) [][]byte {
+// ServiceGetNodeDataQuery assembles the response to a node data query. It is
+// exposed to allow external packages to test protocol behavior.
+func ServiceGetNodeDataQuery(chain *core.BlockChain, bloom *trie.SyncBloom, query GetNodeDataPacket) [][]byte {
 	// Gather state data until the fetch or network limits is reached
 	var (
 		bytes int
@@ -175,14 +182,14 @@ func answerGetNodeDataQuery(backend Backend, query GetNodeDataPacket, peer *Peer
 			break
 		}
 		// Retrieve the requested state entry
-		if bloom := backend.StateBloom(); bloom != nil && !bloom.Contains(hash[:]) {
+		if bloom != nil && !bloom.Contains(hash[:]) {
 			// Only lookup the trie node if there's chance that we actually have it
 			continue
 		}
-		entry, err := backend.Chain().TrieNode(hash)
+		entry, err := chain.TrieNode(hash)
 		if len(entry) == 0 || err != nil {
 			// Read the contract code with prefix only to save unnecessary lookups.
-			entry, err = backend.Chain().ContractCodeWithPrefix(hash)
+			entry, err = chain.ContractCodeWithPrefix(hash)
 		}
 		if err == nil && len(entry) > 0 {
 			nodes = append(nodes, entry)
@@ -198,11 +205,13 @@ func handleGetReceipts66(backend Backend, msg Decoder, peer *Peer) error {
 	if err := msg.Decode(&query); err != nil {
 		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
 	}
-	response := answerGetReceiptsQuery(backend, query.GetReceiptsPacket, peer)
+	response := ServiceGetReceiptsQuery(backend.Chain(), query.GetReceiptsPacket)
 	return peer.ReplyReceiptsRLP(query.RequestId, response)
 }
 
-func answerGetReceiptsQuery(backend Backend, query GetReceiptsPacket, peer *Peer) []rlp.RawValue {
+// ServiceGetReceiptsQuery assembles the response to a receipt query. It is
+// exposed to allow external packages to test protocol behavior.
+func ServiceGetReceiptsQuery(chain *core.BlockChain, query GetReceiptsPacket) []rlp.RawValue {
 	// Gather state data until the fetch or network limits is reached
 	var (
 		bytes    int
@@ -214,9 +223,9 @@ func answerGetReceiptsQuery(backend Backend, query GetReceiptsPacket, peer *Peer
 			break
 		}
 		// Retrieve the requested block's receipts
-		results := backend.Chain().GetReceiptsByHash(hash)
+		results := chain.GetReceiptsByHash(hash)
 		if results == nil {
-			if header := backend.Chain().GetHeaderByHash(hash); header == nil || header.ReceiptHash != types.EmptyRootHash {
+			if header := chain.GetHeaderByHash(hash); header == nil || header.ReceiptHash != types.EmptyRootHash {
 				continue
 			}
 		}
@@ -277,9 +286,11 @@ func handleBlockHeaders66(backend Backend, msg Decoder, peer *Peer) error {
 	if err := msg.Decode(res); err != nil {
 		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
 	}
-	requestTracker.Fulfil(peer.id, peer.version, BlockHeadersMsg, res.RequestId)
+	return peer.dispatchResponse(&Response{
-
+		id:   res.RequestId,
-	return backend.Handle(peer, &res.BlockHeadersPacket)
+		code: BlockHeadersMsg,
+		Res:  &res.BlockHeadersPacket,
+	})
 }
 
 func handleBlockBodies66(backend Backend, msg Decoder, peer *Peer) error {
@@ -288,9 +299,11 @@ func handleBlockBodies66(backend Backend, msg Decoder, peer *Peer) error {
 	if err := msg.Decode(res); err != nil {
 		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
 	}
-	requestTracker.Fulfil(peer.id, peer.version, BlockBodiesMsg, res.RequestId)
+	return peer.dispatchResponse(&Response{
-
+		id:   res.RequestId,
-	return backend.Handle(peer, &res.BlockBodiesPacket)
+		code: BlockBodiesMsg,
+		Res:  &res.BlockBodiesPacket,
+	})
 }
 
 func handleNodeData66(backend Backend, msg Decoder, peer *Peer) error {
@@ -299,9 +312,11 @@ func handleNodeData66(backend Backend, msg Decoder, peer *Peer) error {
 	if err := msg.Decode(res); err != nil {
 		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
 	}
-	requestTracker.Fulfil(peer.id, peer.version, NodeDataMsg, res.RequestId)
+	return peer.dispatchResponse(&Response{
-
+		id:   res.RequestId,
-	return backend.Handle(peer, &res.NodeDataPacket)
+		code: NodeDataMsg,
+		Res:  &res.NodeDataPacket,
+	})
 }
 
 func handleReceipts66(backend Backend, msg Decoder, peer *Peer) error {
@@ -310,9 +325,11 @@ func handleReceipts66(backend Backend, msg Decoder, peer *Peer) error {
 	if err := msg.Decode(res); err != nil {
 		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
 	}
-	requestTracker.Fulfil(peer.id, peer.version, ReceiptsMsg, res.RequestId)
+	return peer.dispatchResponse(&Response{
-
+		id:   res.RequestId,
-	return backend.Handle(peer, &res.ReceiptsPacket)
+		code: ReceiptsMsg,
+		Res:  &res.ReceiptsPacket,
+	})
 }
 
 func handleNewPooledTransactionHashes(backend Backend, msg Decoder, peer *Peer) error {

eth/protocols/eth/peer.go

@@ -84,6 +84,10 @@ type Peer struct {
 	txBroadcast chan []common.Hash // Channel used to queue transaction propagation requests
 	txAnnounce  chan []common.Hash // Channel used to queue transaction announcement requests
 
+	reqDispatch chan *request  // Dispatch channel to send requests and track then until fulfilment
+	reqCancel   chan *cancel   // Dispatch channel to cancel pending requests and untrack them
+	resDispatch chan *response // Dispatch channel to fulfil pending requests and untrack them
+
 	term chan struct{} // Termination channel to stop the broadcasters
 	lock sync.RWMutex  // Mutex protecting the internal fields
 }
@@ -102,6 +106,9 @@ func NewPeer(version uint, p *p2p.Peer, rw p2p.MsgReadWriter, txpool TxPool) *Pe
 		queuedBlockAnns: make(chan *types.Block, maxQueuedBlockAnns),
 		txBroadcast:     make(chan []common.Hash),
 		txAnnounce:      make(chan []common.Hash),
+		reqDispatch:     make(chan *request),
+		reqCancel:       make(chan *cancel),
+		resDispatch:     make(chan *response),
 		txpool:          txpool,
 		term:            make(chan struct{}),
 	}
@@ -109,6 +116,7 @@ func NewPeer(version uint, p *p2p.Peer, rw p2p.MsgReadWriter, txpool TxPool) *Pe
 	go peer.broadcastBlocks()
 	go peer.broadcastTransactions()
 	go peer.announceTransactions()
+	go peer.dispatcher()
 
 	return peer
 }
@@ -323,12 +331,16 @@ func (p *Peer) ReplyReceiptsRLP(id uint64, receipts []rlp.RawValue) error {
 
 // RequestOneHeader is a wrapper around the header query functions to fetch a
 // single header. It is used solely by the fetcher.
-func (p *Peer) RequestOneHeader(hash common.Hash) error {
+func (p *Peer) RequestOneHeader(hash common.Hash, sink chan *Response) (*Request, error) {
 	p.Log().Debug("Fetching single header", "hash", hash)
 	id := rand.Uint64()
 
-	requestTracker.Track(p.id, p.version, GetBlockHeadersMsg, BlockHeadersMsg, id)
+	req := &Request{
-	return p2p.Send(p.rw, GetBlockHeadersMsg, &GetBlockHeadersPacket66{
+		id:   id,
+		sink: sink,
+		code: GetBlockHeadersMsg,
+		want: BlockHeadersMsg,
+		data: &GetBlockHeadersPacket66{
 			RequestId: id,
 			GetBlockHeadersPacket: &GetBlockHeadersPacket{
 				Origin:  HashOrNumber{Hash: hash},
@@ -336,17 +348,26 @@ func (p *Peer) RequestOneHeader(hash common.Hash) error {
 				Skip:    uint64(0),
 				Reverse: false,
 			},
-	})
+		},
+	}
+	if err := p.dispatchRequest(req); err != nil {
+		return nil, err
+	}
+	return req, nil
 }
 
 // RequestHeadersByHash fetches a batch of blocks' headers corresponding to the
 // specified header query, based on the hash of an origin block.
-func (p *Peer) RequestHeadersByHash(origin common.Hash, amount int, skip int, reverse bool) error {
+func (p *Peer) RequestHeadersByHash(origin common.Hash, amount int, skip int, reverse bool, sink chan *Response) (*Request, error) {
 	p.Log().Debug("Fetching batch of headers", "count", amount, "fromhash", origin, "skip", skip, "reverse", reverse)
 	id := rand.Uint64()
 
-	requestTracker.Track(p.id, p.version, GetBlockHeadersMsg, BlockHeadersMsg, id)
+	req := &Request{
-	return p2p.Send(p.rw, GetBlockHeadersMsg, &GetBlockHeadersPacket66{
+		id:   id,
+		sink: sink,
+		code: GetBlockHeadersMsg,
+		want: BlockHeadersMsg,
+		data: &GetBlockHeadersPacket66{
 			RequestId: id,
 			GetBlockHeadersPacket: &GetBlockHeadersPacket{
 				Origin:  HashOrNumber{Hash: origin},
@@ -354,17 +375,26 @@ func (p *Peer) RequestHeadersByHash(origin common.Hash, amount int, skip int, re
 				Skip:    uint64(skip),
 				Reverse: reverse,
 			},
-	})
+		},
+	}
+	if err := p.dispatchRequest(req); err != nil {
+		return nil, err
+	}
+	return req, nil
 }
 
 // RequestHeadersByNumber fetches a batch of blocks' headers corresponding to the
 // specified header query, based on the number of an origin block.
-func (p *Peer) RequestHeadersByNumber(origin uint64, amount int, skip int, reverse bool) error {
+func (p *Peer) RequestHeadersByNumber(origin uint64, amount int, skip int, reverse bool, sink chan *Response) (*Request, error) {
 	p.Log().Debug("Fetching batch of headers", "count", amount, "fromnum", origin, "skip", skip, "reverse", reverse)
 	id := rand.Uint64()
 
-	requestTracker.Track(p.id, p.version, GetBlockHeadersMsg, BlockHeadersMsg, id)
+	req := &Request{
-	return p2p.Send(p.rw, GetBlockHeadersMsg, &GetBlockHeadersPacket66{
+		id:   id,
+		sink: sink,
+		code: GetBlockHeadersMsg,
+		want: BlockHeadersMsg,
+		data: &GetBlockHeadersPacket66{
 			RequestId: id,
 			GetBlockHeadersPacket: &GetBlockHeadersPacket{
 				Origin:  HashOrNumber{Number: origin},
@@ -372,45 +402,77 @@ func (p *Peer) RequestHeadersByNumber(origin uint64, amount int, skip int, rever
 				Skip:    uint64(skip),
 				Reverse: reverse,
 			},
-	})
+		},
+	}
+	if err := p.dispatchRequest(req); err != nil {
+		return nil, err
+	}
+	return req, nil
 }
 
 // RequestBodies fetches a batch of blocks' bodies corresponding to the hashes
 // specified.
-func (p *Peer) RequestBodies(hashes []common.Hash) error {
+func (p *Peer) RequestBodies(hashes []common.Hash, sink chan *Response) (*Request, error) {
 	p.Log().Debug("Fetching batch of block bodies", "count", len(hashes))
 	id := rand.Uint64()
 
-	requestTracker.Track(p.id, p.version, GetBlockBodiesMsg, BlockBodiesMsg, id)
+	req := &Request{
-	return p2p.Send(p.rw, GetBlockBodiesMsg, &GetBlockBodiesPacket66{
+		id:   id,
+		sink: sink,
+		code: GetBlockBodiesMsg,
+		want: BlockBodiesMsg,
+		data: &GetBlockBodiesPacket66{
 			RequestId:            id,
 			GetBlockBodiesPacket: hashes,
-	})
+		},
+	}
+	if err := p.dispatchRequest(req); err != nil {
+		return nil, err
+	}
+	return req, nil
 }
 
 // RequestNodeData fetches a batch of arbitrary data from a node's known state
 // data, corresponding to the specified hashes.
-func (p *Peer) RequestNodeData(hashes []common.Hash) error {
+func (p *Peer) RequestNodeData(hashes []common.Hash, sink chan *Response) (*Request, error) {
 	p.Log().Debug("Fetching batch of state data", "count", len(hashes))
 	id := rand.Uint64()
 
-	requestTracker.Track(p.id, p.version, GetNodeDataMsg, NodeDataMsg, id)
+	req := &Request{
-	return p2p.Send(p.rw, GetNodeDataMsg, &GetNodeDataPacket66{
+		id:   id,
+		sink: sink,
+		code: GetNodeDataMsg,
+		want: NodeDataMsg,
+		data: &GetNodeDataPacket66{
 			RequestId:         id,
 			GetNodeDataPacket: hashes,
-	})
+		},
+	}
+	if err := p.dispatchRequest(req); err != nil {
+		return nil, err
+	}
+	return req, nil
 }
 
 // RequestReceipts fetches a batch of transaction receipts from a remote node.
-func (p *Peer) RequestReceipts(hashes []common.Hash) error {
+func (p *Peer) RequestReceipts(hashes []common.Hash, sink chan *Response) (*Request, error) {
 	p.Log().Debug("Fetching batch of receipts", "count", len(hashes))
 	id := rand.Uint64()
 
-	requestTracker.Track(p.id, p.version, GetReceiptsMsg, ReceiptsMsg, id)
+	req := &Request{
-	return p2p.Send(p.rw, GetReceiptsMsg, &GetReceiptsPacket66{
+		id:   id,
+		sink: sink,
+		code: GetReceiptsMsg,
+		want: ReceiptsMsg,
+		data: &GetReceiptsPacket66{
 			RequestId:         id,
 			GetReceiptsPacket: hashes,
-	})
+		},
+	}
+	if err := p.dispatchRequest(req); err != nil {
+		return nil, err
+	}
+	return req, nil
 }
 
 // RequestTxs fetches a batch of transactions from a remote node.

eth/protocols/snap/handler.go

@@ -99,8 +99,8 @@ func MakeProtocols(backend Backend, dnsdisc enode.Iterator) []p2p.Protocol {
 			Version: version,
 			Length:  protocolLengths[version],
 			Run: func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
-				return backend.RunPeer(newPeer(version, p, rw), func(peer *Peer) error {
+				return backend.RunPeer(NewPeer(version, p, rw), func(peer *Peer) error {
-					return handle(backend, peer)
+					return Handle(backend, peer)
 				})
 			},
 			NodeInfo: func() interface{} {
@@ -116,9 +116,9 @@ func MakeProtocols(backend Backend, dnsdisc enode.Iterator) []p2p.Protocol {
 	return protocols
 }
 
-// handle is the callback invoked to manage the life cycle of a `snap` peer.
+// Handle is the callback invoked to manage the life cycle of a `snap` peer.
 // When this function terminates, the peer is disconnected.
-func handle(backend Backend, peer *Peer) error {
+func Handle(backend Backend, peer *Peer) error {
 	for {
 		if err := handleMessage(backend, peer); err != nil {
 			peer.Log().Debug("Message handling failed in `snap`", "err", err)
@@ -161,17 +161,137 @@ func handleMessage(backend Backend, peer *Peer) error {
 		if err := msg.Decode(&req); err != nil {
 			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
 		}
+		// Service the request, potentially returning nothing in case of errors
+		accounts, proofs := ServiceGetAccountRangeQuery(backend.Chain(), &req)
+
+		// Send back anything accumulated (or empty in case of errors)
+		return p2p.Send(peer.rw, AccountRangeMsg, &AccountRangePacket{
+			ID:       req.ID,
+			Accounts: accounts,
+			Proof:    proofs,
+		})
+
+	case msg.Code == AccountRangeMsg:
+		// A range of accounts arrived to one of our previous requests
+		res := new(AccountRangePacket)
+		if err := msg.Decode(res); err != nil {
+			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+		}
+		// Ensure the range is monotonically increasing
+		for i := 1; i < len(res.Accounts); i++ {
+			if bytes.Compare(res.Accounts[i-1].Hash[:], res.Accounts[i].Hash[:]) >= 0 {
+				return fmt.Errorf("accounts not monotonically increasing: #%d [%x] vs #%d [%x]", i-1, res.Accounts[i-1].Hash[:], i, res.Accounts[i].Hash[:])
+			}
+		}
+		requestTracker.Fulfil(peer.id, peer.version, AccountRangeMsg, res.ID)
+
+		return backend.Handle(peer, res)
+
+	case msg.Code == GetStorageRangesMsg:
+		// Decode the storage retrieval request
+		var req GetStorageRangesPacket
+		if err := msg.Decode(&req); err != nil {
+			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+		}
+		// Service the request, potentially returning nothing in case of errors
+		slots, proofs := ServiceGetStorageRangesQuery(backend.Chain(), &req)
+
+		// Send back anything accumulated (or empty in case of errors)
+		return p2p.Send(peer.rw, StorageRangesMsg, &StorageRangesPacket{
+			ID:    req.ID,
+			Slots: slots,
+			Proof: proofs,
+		})
+
+	case msg.Code == StorageRangesMsg:
+		// A range of storage slots arrived to one of our previous requests
+		res := new(StorageRangesPacket)
+		if err := msg.Decode(res); err != nil {
+			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+		}
+		// Ensure the ranges are monotonically increasing
+		for i, slots := range res.Slots {
+			for j := 1; j < len(slots); j++ {
+				if bytes.Compare(slots[j-1].Hash[:], slots[j].Hash[:]) >= 0 {
+					return fmt.Errorf("storage slots not monotonically increasing for account #%d: #%d [%x] vs #%d [%x]", i, j-1, slots[j-1].Hash[:], j, slots[j].Hash[:])
+				}
+			}
+		}
+		requestTracker.Fulfil(peer.id, peer.version, StorageRangesMsg, res.ID)
+
+		return backend.Handle(peer, res)
+
+	case msg.Code == GetByteCodesMsg:
+		// Decode bytecode retrieval request
+		var req GetByteCodesPacket
+		if err := msg.Decode(&req); err != nil {
+			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+		}
+		// Service the request, potentially returning nothing in case of errors
+		codes := ServiceGetByteCodesQuery(backend.Chain(), &req)
+
+		// Send back anything accumulated (or empty in case of errors)
+		return p2p.Send(peer.rw, ByteCodesMsg, &ByteCodesPacket{
+			ID:    req.ID,
+			Codes: codes,
+		})
+
+	case msg.Code == ByteCodesMsg:
+		// A batch of byte codes arrived to one of our previous requests
+		res := new(ByteCodesPacket)
+		if err := msg.Decode(res); err != nil {
+			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+		}
+		requestTracker.Fulfil(peer.id, peer.version, ByteCodesMsg, res.ID)
+
+		return backend.Handle(peer, res)
+
+	case msg.Code == GetTrieNodesMsg:
+		// Decode trie node retrieval request
+		var req GetTrieNodesPacket
+		if err := msg.Decode(&req); err != nil {
+			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+		}
+		// Service the request, potentially returning nothing in case of errors
+		nodes, err := ServiceGetTrieNodesQuery(backend.Chain(), &req, start)
+		if err != nil {
+			return err
+		}
+		// Send back anything accumulated (or empty in case of errors)
+		return p2p.Send(peer.rw, TrieNodesMsg, &TrieNodesPacket{
+			ID:    req.ID,
+			Nodes: nodes,
+		})
+
+	case msg.Code == TrieNodesMsg:
+		// A batch of trie nodes arrived to one of our previous requests
+		res := new(TrieNodesPacket)
+		if err := msg.Decode(res); err != nil {
+			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+		}
+		requestTracker.Fulfil(peer.id, peer.version, TrieNodesMsg, res.ID)
+
+		return backend.Handle(peer, res)
+
+	default:
+		return fmt.Errorf("%w: %v", errInvalidMsgCode, msg.Code)
+	}
+}
+
+// ServiceGetAccountRangeQuery assembles the response to an account range query.
+// It is exposed to allow external packages to test protocol behavior.
+func ServiceGetAccountRangeQuery(chain *core.BlockChain, req *GetAccountRangePacket) ([]*AccountData, [][]byte) {
 	if req.Bytes > softResponseLimit {
 		req.Bytes = softResponseLimit
 	}
 	// Retrieve the requested state and bail out if non existent
-		tr, err := trie.New(req.Root, backend.Chain().StateCache().TrieDB())
+	tr, err := trie.New(req.Root, chain.StateCache().TrieDB())
 	if err != nil {
-			return p2p.Send(peer.rw, AccountRangeMsg, &AccountRangePacket{ID: req.ID})
+		return nil, nil
 	}
-		it, err := backend.Chain().Snapshots().AccountIterator(req.Root, req.Origin)
+	it, err := chain.Snapshots().AccountIterator(req.Root, req.Origin)
 	if err != nil {
-			return p2p.Send(peer.rw, AccountRangeMsg, &AccountRangePacket{ID: req.ID})
+		return nil, nil
 	}
 	// Iterate over the requested range and pile accounts up
 	var (
@@ -202,47 +322,22 @@ func handleMessage(backend Backend, peer *Peer) error {
 	proof := light.NewNodeSet()
 	if err := tr.Prove(req.Origin[:], 0, proof); err != nil {
 		log.Warn("Failed to prove account range", "origin", req.Origin, "err", err)
-			return p2p.Send(peer.rw, AccountRangeMsg, &AccountRangePacket{ID: req.ID})
+		return nil, nil
 	}
 	if last != (common.Hash{}) {
 		if err := tr.Prove(last[:], 0, proof); err != nil {
 			log.Warn("Failed to prove account range", "last", last, "err", err)
-				return p2p.Send(peer.rw, AccountRangeMsg, &AccountRangePacket{ID: req.ID})
+			return nil, nil
 		}
 	}
 	var proofs [][]byte
 	for _, blob := range proof.NodeList() {
 		proofs = append(proofs, blob)
 	}
-		// Send back anything accumulated
+	return accounts, proofs
-		return p2p.Send(peer.rw, AccountRangeMsg, &AccountRangePacket{
+}
-			ID:       req.ID,
-			Accounts: accounts,
-			Proof:    proofs,
-		})
 
-	case msg.Code == AccountRangeMsg:
+func ServiceGetStorageRangesQuery(chain *core.BlockChain, req *GetStorageRangesPacket) ([][]*StorageData, [][]byte) {
-		// A range of accounts arrived to one of our previous requests
-		res := new(AccountRangePacket)
-		if err := msg.Decode(res); err != nil {
-			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
-		}
-		// Ensure the range is monotonically increasing
-		for i := 1; i < len(res.Accounts); i++ {
-			if bytes.Compare(res.Accounts[i-1].Hash[:], res.Accounts[i].Hash[:]) >= 0 {
-				return fmt.Errorf("accounts not monotonically increasing: #%d [%x] vs #%d [%x]", i-1, res.Accounts[i-1].Hash[:], i, res.Accounts[i].Hash[:])
-			}
-		}
-		requestTracker.Fulfil(peer.id, peer.version, AccountRangeMsg, res.ID)
-
-		return backend.Handle(peer, res)
-
-	case msg.Code == GetStorageRangesMsg:
-		// Decode the storage retrieval request
-		var req GetStorageRangesPacket
-		if err := msg.Decode(&req); err != nil {
-			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
-		}
 	if req.Bytes > softResponseLimit {
 		req.Bytes = softResponseLimit
 	}
@@ -275,9 +370,9 @@ func handleMessage(backend Backend, peer *Peer) error {
 			limit, req.Limit = common.BytesToHash(req.Limit), nil
 		}
 		// Retrieve the requested state and bail out if non existent
-			it, err := backend.Chain().Snapshots().StorageIterator(req.Root, account, origin)
+		it, err := chain.Snapshots().StorageIterator(req.Root, account, origin)
 		if err != nil {
-				return p2p.Send(peer.rw, StorageRangesMsg, &StorageRangesPacket{ID: req.ID})
+			return nil, nil
 		}
 		// Iterate over the requested range and pile slots up
 		var (
@@ -315,27 +410,27 @@ func handleMessage(backend Backend, peer *Peer) error {
 		if origin != (common.Hash{}) || abort {
 			// Request started at a non-zero hash or was capped prematurely, add
 			// the endpoint Merkle proofs
-				accTrie, err := trie.New(req.Root, backend.Chain().StateCache().TrieDB())
+			accTrie, err := trie.New(req.Root, chain.StateCache().TrieDB())
 			if err != nil {
-					return p2p.Send(peer.rw, StorageRangesMsg, &StorageRangesPacket{ID: req.ID})
+				return nil, nil
 			}
 			var acc types.StateAccount
 			if err := rlp.DecodeBytes(accTrie.Get(account[:]), &acc); err != nil {
-					return p2p.Send(peer.rw, StorageRangesMsg, &StorageRangesPacket{ID: req.ID})
+				return nil, nil
 			}
-				stTrie, err := trie.New(acc.Root, backend.Chain().StateCache().TrieDB())
+			stTrie, err := trie.New(acc.Root, chain.StateCache().TrieDB())
 			if err != nil {
-					return p2p.Send(peer.rw, StorageRangesMsg, &StorageRangesPacket{ID: req.ID})
+				return nil, nil
 			}
 			proof := light.NewNodeSet()
 			if err := stTrie.Prove(origin[:], 0, proof); err != nil {
 				log.Warn("Failed to prove storage range", "origin", req.Origin, "err", err)
-					return p2p.Send(peer.rw, StorageRangesMsg, &StorageRangesPacket{ID: req.ID})
+				return nil, nil
 			}
 			if last != (common.Hash{}) {
 				if err := stTrie.Prove(last[:], 0, proof); err != nil {
 					log.Warn("Failed to prove storage range", "last", last, "err", err)
-						return p2p.Send(peer.rw, StorageRangesMsg, &StorageRangesPacket{ID: req.ID})
+					return nil, nil
 				}
 			}
 			for _, blob := range proof.NodeList() {
@@ -347,37 +442,12 @@ func handleMessage(backend Backend, peer *Peer) error {
 			break
 		}
 	}
-		// Send back anything accumulated
+	return slots, proofs
-		return p2p.Send(peer.rw, StorageRangesMsg, &StorageRangesPacket{
+}
-			ID:    req.ID,
-			Slots: slots,
-			Proof: proofs,
-		})
 
-	case msg.Code == StorageRangesMsg:
+// ServiceGetByteCodesQuery assembles the response to a byte codes query.
-		// A range of storage slots arrived to one of our previous requests
+// It is exposed to allow external packages to test protocol behavior.
-		res := new(StorageRangesPacket)
+func ServiceGetByteCodesQuery(chain *core.BlockChain, req *GetByteCodesPacket) [][]byte {
-		if err := msg.Decode(res); err != nil {
-			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
-		}
-		// Ensure the ranges are monotonically increasing
-		for i, slots := range res.Slots {
-			for j := 1; j < len(slots); j++ {
-				if bytes.Compare(slots[j-1].Hash[:], slots[j].Hash[:]) >= 0 {
-					return fmt.Errorf("storage slots not monotonically increasing for account #%d: #%d [%x] vs #%d [%x]", i, j-1, slots[j-1].Hash[:], j, slots[j].Hash[:])
-				}
-			}
-		}
-		requestTracker.Fulfil(peer.id, peer.version, StorageRangesMsg, res.ID)
-
-		return backend.Handle(peer, res)
-
-	case msg.Code == GetByteCodesMsg:
-		// Decode bytecode retrieval request
-		var req GetByteCodesPacket
-		if err := msg.Decode(&req); err != nil {
-			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
-		}
 	if req.Bytes > softResponseLimit {
 		req.Bytes = softResponseLimit
 	}
@@ -394,7 +464,7 @@ func handleMessage(backend Backend, peer *Peer) error {
 			// Peers should not request the empty code, but if they do, at
 			// least sent them back a correct response without db lookups
 			codes = append(codes, []byte{})
-			} else if blob, err := backend.Chain().ContractCode(hash); err == nil {
+		} else if blob, err := chain.ContractCode(hash); err == nil {
 			codes = append(codes, blob)
 			bytes += uint64(len(blob))
 		}
@@ -402,46 +472,30 @@ func handleMessage(backend Backend, peer *Peer) error {
 			break
 		}
 	}
-		// Send back anything accumulated
+	return codes
-		return p2p.Send(peer.rw, ByteCodesMsg, &ByteCodesPacket{
+}
-			ID:    req.ID,
-			Codes: codes,
-		})
 
-	case msg.Code == ByteCodesMsg:
+// ServiceGetTrieNodesQuery assembles the response to a trie nodes query.
-		// A batch of byte codes arrived to one of our previous requests
+// It is exposed to allow external packages to test protocol behavior.
-		res := new(ByteCodesPacket)
+func ServiceGetTrieNodesQuery(chain *core.BlockChain, req *GetTrieNodesPacket, start time.Time) ([][]byte, error) {
-		if err := msg.Decode(res); err != nil {
-			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
-		}
-		requestTracker.Fulfil(peer.id, peer.version, ByteCodesMsg, res.ID)
-
-		return backend.Handle(peer, res)
-
-	case msg.Code == GetTrieNodesMsg:
-		// Decode trie node retrieval request
-		var req GetTrieNodesPacket
-		if err := msg.Decode(&req); err != nil {
-			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
-		}
 	if req.Bytes > softResponseLimit {
 		req.Bytes = softResponseLimit
 	}
 	// Make sure we have the state associated with the request
-		triedb := backend.Chain().StateCache().TrieDB()
+	triedb := chain.StateCache().TrieDB()
 
 	accTrie, err := trie.NewSecure(req.Root, triedb)
 	if err != nil {
 		// We don't have the requested state available, bail out
-			return p2p.Send(peer.rw, TrieNodesMsg, &TrieNodesPacket{ID: req.ID})
+		return nil, nil
 	}
-		snap := backend.Chain().Snapshots().Snapshot(req.Root)
+	snap := chain.Snapshots().Snapshot(req.Root)
 	if snap == nil {
 		// We don't have the requested state snapshotted yet, bail out.
 		// In reality we could still serve using the account and storage
 		// tries only, but let's protect the node a bit while it's doing
 		// snapshot generation.
-			return p2p.Send(peer.rw, TrieNodesMsg, &TrieNodesPacket{ID: req.ID})
+		return nil, nil
 	}
 	// Retrieve trie nodes until the packet size limit is reached
 	var (
@@ -453,7 +507,7 @@ func handleMessage(backend Backend, peer *Peer) error {
 		switch len(pathset) {
 		case 0:
 			// Ensure we penalize invalid requests
-				return fmt.Errorf("%w: zero-item pathset requested", errBadRequest)
+			return nil, fmt.Errorf("%w: zero-item pathset requested", errBadRequest)
 
 		case 1:
 			// If we're only retrieving an account trie node, fetch it directly
@@ -497,25 +551,7 @@ func handleMessage(backend Backend, peer *Peer) error {
 			break
 		}
 	}
-		// Send back anything accumulated
+	return nodes, nil
-		return p2p.Send(peer.rw, TrieNodesMsg, &TrieNodesPacket{
-			ID:    req.ID,
-			Nodes: nodes,
-		})
-
-	case msg.Code == TrieNodesMsg:
-		// A batch of trie nodes arrived to one of our previous requests
-		res := new(TrieNodesPacket)
-		if err := msg.Decode(res); err != nil {
-			return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
-		}
-		requestTracker.Fulfil(peer.id, peer.version, TrieNodesMsg, res.ID)
-
-		return backend.Handle(peer, res)
-
-	default:
-		return fmt.Errorf("%w: %v", errInvalidMsgCode, msg.Code)
-	}
 }
 
 // NodeInfo represents a short summary of the `snap` sub-protocol metadata

eth/protocols/snap/peer.go

@@ -33,9 +33,9 @@ type Peer struct {
 	logger log.Logger // Contextual logger with the peer id injected
 }
 
-// newPeer create a wrapper for a network connection and negotiated  protocol
+// NewPeer create a wrapper for a network connection and negotiated  protocol
 // version.
-func newPeer(version uint, p *p2p.Peer, rw p2p.MsgReadWriter) *Peer {
+func NewPeer(version uint, p *p2p.Peer, rw p2p.MsgReadWriter) *Peer {
 	id := p.ID().String()
 	return &Peer{
 		id:      id,

eth/protocols/snap/protocol.go

@@ -27,7 +27,7 @@ import (
 
 // Constants to match up protocol versions and messages
 const (
-	snap1 = 1
+	SNAP1 = 1
 )
 
 // ProtocolName is the official short name of the `snap` protocol used during
@@ -36,11 +36,11 @@ const ProtocolName = "snap"
 
 // ProtocolVersions are the supported versions of the `snap` protocol (first
 // is primary).
-var ProtocolVersions = []uint{snap1}
+var ProtocolVersions = []uint{SNAP1}
 
 // protocolLengths are the number of implemented message corresponding to
 // different protocol versions.
-var protocolLengths = map[uint]uint64{snap1: 8}
+var protocolLengths = map[uint]uint64{SNAP1: 8}
 
 // maxMessageSize is the maximum cap on the size of a protocol message.
 const maxMessageSize = 10 * 1024 * 1024

eth/protocols/snap/sync.go

@@ -325,10 +325,10 @@ type healTask struct {
 	codeTasks map[common.Hash]struct{}      // Set of byte code tasks currently queued for retrieval
 }
 
-// syncProgress is a database entry to allow suspending and resuming a snapshot state
+// SyncProgress is a database entry to allow suspending and resuming a snapshot state
 // sync. Opposed to full and fast sync, there is no way to restart a suspended
 // snap sync without prior knowledge of the suspension point.
-type syncProgress struct {
+type SyncProgress struct {
 	Tasks []*accountTask // The suspended account tasks (contract tasks within)
 
 	// Status report during syncing phase
@@ -342,12 +342,15 @@ type syncProgress struct {
 	// Status report during healing phase
 	TrienodeHealSynced uint64             // Number of state trie nodes downloaded
 	TrienodeHealBytes  common.StorageSize // Number of state trie bytes persisted to disk
-	TrienodeHealDups   uint64             // Number of state trie nodes already processed
-	TrienodeHealNops   uint64             // Number of state trie nodes not requested
 	BytecodeHealSynced uint64             // Number of bytecodes downloaded
 	BytecodeHealBytes  common.StorageSize // Number of bytecodes persisted to disk
-	BytecodeHealDups   uint64             // Number of bytecodes already processed
+}
-	BytecodeHealNops   uint64             // Number of bytecodes not requested
+
+// SyncPending is analogous to SyncProgress, but it's used to report on pending
+// ephemeral sync progress that doesn't get persisted into the database.
+type SyncPending struct {
+	TrienodeHeal uint64 // Number of state trie nodes pending
+	BytecodeHeal uint64 // Number of bytecodes pending
 }
 
 // SyncPeer abstracts out the methods required for a peer to be synced against
@@ -671,7 +674,7 @@ func (s *Syncer) Sync(root common.Hash, cancel chan struct{}) error {
 // loadSyncStatus retrieves a previously aborted sync status from the database,
 // or generates a fresh one if none is available.
 func (s *Syncer) loadSyncStatus() {
-	var progress syncProgress
+	var progress SyncProgress
 
 	if status := rawdb.ReadSnapshotSyncStatus(s.db); status != nil {
 		if err := json.Unmarshal(status, &progress); err != nil {
@@ -775,7 +778,7 @@ func (s *Syncer) saveSyncStatus() {
 		}
 	}
 	// Store the actual progress markers
-	progress := &syncProgress{
+	progress := &SyncProgress{
 		Tasks:              s.tasks,
 		AccountSynced:      s.accountSynced,
 		AccountBytes:       s.accountBytes,
@@ -795,6 +798,31 @@ func (s *Syncer) saveSyncStatus() {
 	rawdb.WriteSnapshotSyncStatus(s.db, status)
 }
 
+// Progress returns the snap sync status statistics.
+func (s *Syncer) Progress() (*SyncProgress, *SyncPending) {
+	s.lock.Lock()
+	defer s.lock.Unlock()
+
+	progress := &SyncProgress{
+		AccountSynced:      s.accountSynced,
+		AccountBytes:       s.accountBytes,
+		BytecodeSynced:     s.bytecodeSynced,
+		BytecodeBytes:      s.bytecodeBytes,
+		StorageSynced:      s.storageSynced,
+		StorageBytes:       s.storageBytes,
+		TrienodeHealSynced: s.trienodeHealSynced,
+		TrienodeHealBytes:  s.trienodeHealBytes,
+		BytecodeHealSynced: s.bytecodeHealSynced,
+		BytecodeHealBytes:  s.bytecodeHealBytes,
+	}
+	pending := new(SyncPending)
+	if s.healer != nil {
+		pending.TrienodeHeal = uint64(len(s.healer.trieTasks))
+		pending.BytecodeHeal = uint64(len(s.healer.codeTasks))
+	}
+	return progress, pending
+}
+
 // cleanAccountTasks removes account range retrieval tasks that have already been
 // completed.
 func (s *Syncer) cleanAccountTasks() {

eth/sync.go

@@ -165,10 +165,7 @@ func (cs *chainSyncer) nextSyncOp() *chainSyncOp {
 		return nil
 	}
 	mode, ourTD := cs.modeAndLocalHead()
-	if mode == downloader.FastSync && atomic.LoadUint32(&cs.handler.snapSync) == 1 {
+
-		// Fast sync via the snap protocol
-		mode = downloader.SnapSync
-	}
 	op := peerToSyncOp(mode, peer)
 	if op.td.Cmp(ourTD) <= 0 {
 		return nil // We're in sync.
@@ -182,19 +179,19 @@ func peerToSyncOp(mode downloader.SyncMode, p *eth.Peer) *chainSyncOp {
 }
 
 func (cs *chainSyncer) modeAndLocalHead() (downloader.SyncMode, *big.Int) {
-	// If we're in fast sync mode, return that directly
+	// If we're in snap sync mode, return that directly
-	if atomic.LoadUint32(&cs.handler.fastSync) == 1 {
+	if atomic.LoadUint32(&cs.handler.snapSync) == 1 {
 		block := cs.handler.chain.CurrentFastBlock()
 		td := cs.handler.chain.GetTd(block.Hash(), block.NumberU64())
-		return downloader.FastSync, td
+		return downloader.SnapSync, td
 	}
 	// We are probably in full sync, but we might have rewound to before the
-	// fast sync pivot, check if we should reenable
+	// snap sync pivot, check if we should reenable
 	if pivot := rawdb.ReadLastPivotNumber(cs.handler.database); pivot != nil {
 		if head := cs.handler.chain.CurrentBlock(); head.NumberU64() < *pivot {
 			block := cs.handler.chain.CurrentFastBlock()
 			td := cs.handler.chain.GetTd(block.Hash(), block.NumberU64())
-			return downloader.FastSync, td
+			return downloader.SnapSync, td
 		}
 	}
 	// Nope, we're really full syncing
@@ -211,15 +208,15 @@ func (cs *chainSyncer) startSync(op *chainSyncOp) {
 
 // doSync synchronizes the local blockchain with a remote peer.
 func (h *handler) doSync(op *chainSyncOp) error {
-	if op.mode == downloader.FastSync || op.mode == downloader.SnapSync {
+	if op.mode == downloader.SnapSync {
-		// Before launch the fast sync, we have to ensure user uses the same
+		// Before launch the snap sync, we have to ensure user uses the same
 		// txlookup limit.
-		// The main concern here is: during the fast sync Geth won't index the
+		// The main concern here is: during the snap sync Geth won't index the
 		// block(generate tx indices) before the HEAD-limit. But if user changes
-		// the limit in the next fast sync(e.g. user kill Geth manually and
+		// the limit in the next snap sync(e.g. user kill Geth manually and
 		// restart) then it will be hard for Geth to figure out the oldest block
 		// has been indexed. So here for the user-experience wise, it's non-optimal
-		// that user can't change limit during the fast sync. If changed, Geth
+		// that user can't change limit during the snap sync. If changed, Geth
 		// will just blindly use the original one.
 		limit := h.chain.TxLookupLimit()
 		if stored := rawdb.ReadFastTxLookupLimit(h.database); stored == nil {
@@ -229,15 +226,11 @@ func (h *handler) doSync(op *chainSyncOp) error {
 			log.Warn("Update txLookup limit", "provided", limit, "updated", *stored)
 		}
 	}
-	// Run the sync cycle, and disable fast sync if we're past the pivot block
+	// Run the sync cycle, and disable snap sync if we're past the pivot block
 	err := h.downloader.Synchronise(op.peer.ID(), op.head, op.td, op.mode)
 	if err != nil {
 		return err
 	}
-	if atomic.LoadUint32(&h.fastSync) == 1 {
-		log.Info("Fast sync complete, auto disabling")
-		atomic.StoreUint32(&h.fastSync, 0)
-	}
 	if atomic.LoadUint32(&h.snapSync) == 1 {
 		log.Info("Snap sync complete, auto disabling")
 		atomic.StoreUint32(&h.snapSync, 0)

eth/sync_test.go

@@ -23,57 +23,74 @@ import (
 
 	"github.com/ethereum/go-ethereum/eth/downloader"
 	"github.com/ethereum/go-ethereum/eth/protocols/eth"
+	"github.com/ethereum/go-ethereum/eth/protocols/snap"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 )
 
-// Tests that fast sync is disabled after a successful sync cycle.
+// Tests that snap sync is disabled after a successful sync cycle.
-func TestFastSyncDisabling66(t *testing.T) { testFastSyncDisabling(t, eth.ETH66) }
+func TestSnapSyncDisabling66(t *testing.T) { testSnapSyncDisabling(t, eth.ETH66, snap.SNAP1) }
 
-// Tests that fast sync gets disabled as soon as a real block is successfully
+// Tests that snap sync gets disabled as soon as a real block is successfully
 // imported into the blockchain.
-func testFastSyncDisabling(t *testing.T, protocol uint) {
+func testSnapSyncDisabling(t *testing.T, ethVer uint, snapVer uint) {
 	t.Parallel()
 
-	// Create an empty handler and ensure it's in fast sync mode
+	// Create an empty handler and ensure it's in snap sync mode
 	empty := newTestHandler()
-	if atomic.LoadUint32(&empty.handler.fastSync) == 0 {
+	if atomic.LoadUint32(&empty.handler.snapSync) == 0 {
-		t.Fatalf("fast sync disabled on pristine blockchain")
+		t.Fatalf("snap sync disabled on pristine blockchain")
 	}
 	defer empty.close()
 
-	// Create a full handler and ensure fast sync ends up disabled
+	// Create a full handler and ensure snap sync ends up disabled
 	full := newTestHandlerWithBlocks(1024)
-	if atomic.LoadUint32(&full.handler.fastSync) == 1 {
+	if atomic.LoadUint32(&full.handler.snapSync) == 1 {
-		t.Fatalf("fast sync not disabled on non-empty blockchain")
+		t.Fatalf("snap sync not disabled on non-empty blockchain")
 	}
 	defer full.close()
 
-	// Sync up the two handlers
+	// Sync up the two handlers via both `eth` and `snap`
-	emptyPipe, fullPipe := p2p.MsgPipe()
+	caps := []p2p.Cap{{Name: "eth", Version: ethVer}, {Name: "snap", Version: snapVer}}
-	defer emptyPipe.Close()
-	defer fullPipe.Close()
 
-	emptyPeer := eth.NewPeer(protocol, p2p.NewPeer(enode.ID{1}, "", nil), emptyPipe, empty.txpool)
+	emptyPipeEth, fullPipeEth := p2p.MsgPipe()
-	fullPeer := eth.NewPeer(protocol, p2p.NewPeer(enode.ID{2}, "", nil), fullPipe, full.txpool)
+	defer emptyPipeEth.Close()
-	defer emptyPeer.Close()
+	defer fullPipeEth.Close()
-	defer fullPeer.Close()
 
-	go empty.handler.runEthPeer(emptyPeer, func(peer *eth.Peer) error {
+	emptyPeerEth := eth.NewPeer(ethVer, p2p.NewPeer(enode.ID{1}, "", caps), emptyPipeEth, empty.txpool)
+	fullPeerEth := eth.NewPeer(ethVer, p2p.NewPeer(enode.ID{2}, "", caps), fullPipeEth, full.txpool)
+	defer emptyPeerEth.Close()
+	defer fullPeerEth.Close()
+
+	go empty.handler.runEthPeer(emptyPeerEth, func(peer *eth.Peer) error {
 		return eth.Handle((*ethHandler)(empty.handler), peer)
 	})
-	go full.handler.runEthPeer(fullPeer, func(peer *eth.Peer) error {
+	go full.handler.runEthPeer(fullPeerEth, func(peer *eth.Peer) error {
 		return eth.Handle((*ethHandler)(full.handler), peer)
 	})
+
+	emptyPipeSnap, fullPipeSnap := p2p.MsgPipe()
+	defer emptyPipeSnap.Close()
+	defer fullPipeSnap.Close()
+
+	emptyPeerSnap := snap.NewPeer(snapVer, p2p.NewPeer(enode.ID{1}, "", caps), emptyPipeSnap)
+	fullPeerSnap := snap.NewPeer(snapVer, p2p.NewPeer(enode.ID{2}, "", caps), fullPipeSnap)
+
+	go empty.handler.runSnapExtension(emptyPeerSnap, func(peer *snap.Peer) error {
+		return snap.Handle((*snapHandler)(empty.handler), peer)
+	})
+	go full.handler.runSnapExtension(fullPeerSnap, func(peer *snap.Peer) error {
+		return snap.Handle((*snapHandler)(full.handler), peer)
+	})
 	// Wait a bit for the above handlers to start
 	time.Sleep(250 * time.Millisecond)
 
-	// Check that fast sync was disabled
+	// Check that snap sync was disabled
-	op := peerToSyncOp(downloader.FastSync, empty.handler.peers.peerWithHighestTD())
+	op := peerToSyncOp(downloader.SnapSync, empty.handler.peers.peerWithHighestTD())
 	if err := empty.handler.doSync(op); err != nil {
 		t.Fatal("sync failed:", err)
 	}
-	if atomic.LoadUint32(&empty.handler.fastSync) == 1 {
+	if atomic.LoadUint32(&empty.handler.snapSync) == 1 {
-		t.Fatalf("fast sync not disabled after successful synchronisation")
+		t.Fatalf("snap sync not disabled after successful synchronisation")
 	}
 }

ethclient/ethclient.go

@@ -286,14 +286,6 @@ func (ec *Client) TransactionReceipt(ctx context.Context, txHash common.Hash) (*
 	return r, err
 }
 
-type rpcProgress struct {
-	StartingBlock hexutil.Uint64
-	CurrentBlock  hexutil.Uint64
-	HighestBlock  hexutil.Uint64
-	PulledStates  hexutil.Uint64
-	KnownStates   hexutil.Uint64
-}
-
 // SyncProgress retrieves the current progress of the sync algorithm. If there's
 // no sync currently running, it returns nil.
 func (ec *Client) SyncProgress(ctx context.Context) (*ethereum.SyncProgress, error) {
@@ -306,17 +298,11 @@ func (ec *Client) SyncProgress(ctx context.Context) (*ethereum.SyncProgress, err
 	if err := json.Unmarshal(raw, &syncing); err == nil {
 		return nil, nil // Not syncing (always false)
 	}
-	var progress *rpcProgress
+	var progress *ethereum.SyncProgress
 	if err := json.Unmarshal(raw, &progress); err != nil {
 		return nil, err
 	}
-	return &ethereum.SyncProgress{
+	return progress, nil
-		StartingBlock: uint64(progress.StartingBlock),
-		CurrentBlock:  uint64(progress.CurrentBlock),
-		HighestBlock:  uint64(progress.HighestBlock),
-		PulledStates:  uint64(progress.PulledStates),
-		KnownStates:   uint64(progress.KnownStates),
-	}, nil
 }
 
 // SubscribeNewHead subscribes to notifications about the current blockchain head

graphql/graphql.go

@@ -1220,23 +1220,47 @@ type SyncState struct {
 func (s *SyncState) StartingBlock() hexutil.Uint64 {
 	return hexutil.Uint64(s.progress.StartingBlock)
 }
-
 func (s *SyncState) CurrentBlock() hexutil.Uint64 {
 	return hexutil.Uint64(s.progress.CurrentBlock)
 }
-
 func (s *SyncState) HighestBlock() hexutil.Uint64 {
 	return hexutil.Uint64(s.progress.HighestBlock)
 }
-
+func (s *SyncState) SyncedAccounts() hexutil.Uint64 {
-func (s *SyncState) PulledStates() *hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.SyncedAccounts)
-	ret := hexutil.Uint64(s.progress.PulledStates)
-	return &ret
 }
-
+func (s *SyncState) SyncedAccountBytes() hexutil.Uint64 {
-func (s *SyncState) KnownStates() *hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.SyncedAccountBytes)
-	ret := hexutil.Uint64(s.progress.KnownStates)
+}
-	return &ret
+func (s *SyncState) SyncedBytecodes() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.SyncedBytecodes)
+}
+func (s *SyncState) SyncedBytecodeBytes() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.SyncedBytecodeBytes)
+}
+func (s *SyncState) SyncedStorage() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.SyncedStorage)
+}
+func (s *SyncState) SyncedStorageBytes() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.SyncedStorageBytes)
+}
+func (s *SyncState) HealedTrienodes() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.HealedTrienodes)
+}
+func (s *SyncState) HealedTrienodeBytes() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.HealedTrienodeBytes)
+}
+func (s *SyncState) HealedBytecodes() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.HealedBytecodes)
+}
+func (s *SyncState) HealedBytecodeBytes() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.HealedBytecodeBytes)
+}
+func (s *SyncState) HealingTrienodes() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.HealingTrienodes)
+}
+func (s *SyncState) HealingBytecode() hexutil.Uint64 {
+	return hexutil.Uint64(s.progress.HealingBytecode)
 }
 
 // Syncing returns false in case the node is currently not syncing with the network. It can be up to date or has not
@@ -1244,8 +1268,18 @@ func (s *SyncState) KnownStates() *hexutil.Uint64 {
 // - startingBlock:       block number this node started to synchronise from
 // - currentBlock:        block number this node is currently importing
 // - highestBlock:        block number of the highest block header this node has received from peers
-// - pulledStates:  number of state entries processed until now
+// - syncedAccounts:      number of accounts downloaded
-// - knownStates:   number of known state entries that still need to be pulled
+// - syncedAccountBytes:  number of account trie bytes persisted to disk
+// - syncedBytecodes:     number of bytecodes downloaded
+// - syncedBytecodeBytes: number of bytecode bytes downloaded
+// - syncedStorage:       number of storage slots downloaded
+// - syncedStorageBytes:  number of storage trie bytes persisted to disk
+// - healedTrienodes:     number of state trie nodes downloaded
+// - healedTrienodeBytes: number of state trie bytes persisted to disk
+// - healedBytecodes:     number of bytecodes downloaded
+// - healedBytecodeBytes: number of bytecodes persisted to disk
+// - healingTrienodes:    number of state trie nodes pending
+// - healingBytecode:     number of bytecodes pending
 func (r *Resolver) Syncing() (*SyncState, error) {
 	progress := r.backend.SyncProgress()
 

graphql/schema.go

@@ -297,12 +297,6 @@ const schema string = `
         currentBlock: Long!
         # HighestBlock is the latest known block number.
         highestBlock: Long!
-        # PulledStates is the number of state entries fetched so far, or null
-        # if this is not known or not relevant.
-        pulledStates: Long
-        # KnownStates is the number of states the node knows of so far, or null
-        # if this is not known or not relevant.
-        knownStates: Long
     }
 
     # Pending represents the current pending state.

interfaces.go

@@ -101,8 +101,22 @@ type SyncProgress struct {
 	StartingBlock uint64 // Block number where sync began
 	CurrentBlock  uint64 // Current block number where sync is at
 	HighestBlock  uint64 // Highest alleged block number in the chain
-	PulledStates  uint64 // Number of state trie entries already downloaded
+
-	KnownStates   uint64 // Total number of state trie entries known about
+	// Fields belonging to snap sync
+	SyncedAccounts      uint64 // Number of accounts downloaded
+	SyncedAccountBytes  uint64 // Number of account trie bytes persisted to disk
+	SyncedBytecodes     uint64 // Number of bytecodes downloaded
+	SyncedBytecodeBytes uint64 // Number of bytecode bytes downloaded
+	SyncedStorage       uint64 // Number of storage slots downloaded
+	SyncedStorageBytes  uint64 // Number of storage trie bytes persisted to disk
+
+	HealedTrienodes     uint64 // Number of state trie nodes downloaded
+	HealedTrienodeBytes uint64 // Number of state trie bytes persisted to disk
+	HealedBytecodes     uint64 // Number of bytecodes downloaded
+	HealedBytecodeBytes uint64 // Number of bytecodes persisted to disk
+
+	HealingTrienodes uint64 // Number of state trie nodes pending
+	HealingBytecode  uint64 // Number of bytecodes pending
 }
 
 // ChainSyncReader wraps access to the node's current sync status. If there's no

internal/ethapi/api.go

@@ -134,8 +134,18 @@ func (s *PublicEthereumAPI) Syncing() (interface{}, error) {
 		"startingBlock":       hexutil.Uint64(progress.StartingBlock),
 		"currentBlock":        hexutil.Uint64(progress.CurrentBlock),
 		"highestBlock":        hexutil.Uint64(progress.HighestBlock),
-		"pulledStates":  hexutil.Uint64(progress.PulledStates),
+		"syncedAccounts":      hexutil.Uint64(progress.SyncedAccounts),
-		"knownStates":   hexutil.Uint64(progress.KnownStates),
+		"syncedAccountBytes":  hexutil.Uint64(progress.SyncedAccountBytes),
+		"syncedBytecodes":     hexutil.Uint64(progress.SyncedBytecodes),
+		"syncedBytecodeBytes": hexutil.Uint64(progress.SyncedBytecodeBytes),
+		"syncedStorage":       hexutil.Uint64(progress.SyncedStorage),
+		"syncedStorageBytes":  hexutil.Uint64(progress.SyncedStorageBytes),
+		"healedTrienodes":     hexutil.Uint64(progress.HealedTrienodes),
+		"healedTrienodeBytes": hexutil.Uint64(progress.HealedTrienodeBytes),
+		"healedBytecodes":     hexutil.Uint64(progress.HealedBytecodes),
+		"healedBytecodeBytes": hexutil.Uint64(progress.HealedBytecodeBytes),
+		"healingTrienodes":    hexutil.Uint64(progress.HealingTrienodes),
+		"healingBytecode":     hexutil.Uint64(progress.HealingBytecode),
 	}, nil
 }
 

internal/jsre/deps/web3.js

@@ -3949,10 +3949,18 @@ var outputSyncingFormatter = function(result) {
     result.startingBlock = utils.toDecimal(result.startingBlock);
     result.currentBlock = utils.toDecimal(result.currentBlock);
     result.highestBlock = utils.toDecimal(result.highestBlock);
-    if (result.knownStates) {
+    result.syncedAccounts = utils.toDecimal(result.syncedAccounts);
-        result.knownStates = utils.toDecimal(result.knownStates);
+    result.syncedAccountBytes = utils.toDecimal(result.syncedAccountBytes);
-        result.pulledStates = utils.toDecimal(result.pulledStates);
+    result.syncedBytecodes = utils.toDecimal(result.syncedBytecodes);
-    }
+    result.syncedBytecodeBytes = utils.toDecimal(result.syncedBytecodeBytes);
+    result.syncedStorage = utils.toDecimal(result.syncedStorage);
+    result.syncedStorageBytes = utils.toDecimal(result.syncedStorageBytes);
+    result.healedTrienodes = utils.toDecimal(result.healedTrienodes);
+    result.healedTrienodeBytes = utils.toDecimal(result.healedTrienodeBytes);
+    result.healedBytecodes = utils.toDecimal(result.healedBytecodes);
+    result.healedBytecodeBytes = utils.toDecimal(result.healedBytecodeBytes);
+    result.healingTrienodes = utils.toDecimal(result.healingTrienodes);
+    result.healingBytecode = utils.toDecimal(result.healingBytecode);
 
     return result;
 };

les/downloader/downloader.go

@@ -231,9 +231,9 @@ func New(checkpoint uint64, stateDb ethdb.Database, stateBloom *trie.SyncBloom,
 		stateCh:        make(chan dataPack),
 		SnapSyncer:     snap.NewSyncer(stateDb),
 		stateSyncStart: make(chan *stateSync),
-		syncStatsState: stateSyncStats{
+		//syncStatsState: stateSyncStats{
-			processed: rawdb.ReadFastTrieProgress(stateDb),
+		//	processed: rawdb.ReadFastTrieProgress(stateDb),
-		},
+		//},
 		trackStateReq: make(chan *stateReq),
 	}
 	go dl.stateFetcher()
@@ -268,8 +268,8 @@ func (d *Downloader) Progress() ethereum.SyncProgress {
 		StartingBlock: d.syncStatsChainOrigin,
 		CurrentBlock:  current,
 		HighestBlock:  d.syncStatsChainHeight,
-		PulledStates:  d.syncStatsState.processed,
+		//PulledStates:  d.syncStatsState.processed,
-		KnownStates:   d.syncStatsState.processed + d.syncStatsState.pending,
+		//KnownStates:   d.syncStatsState.processed + d.syncStatsState.pending,
 	}
 }
 

les/downloader/downloader_test.go

@@ -1207,8 +1207,8 @@ func checkProgress(t *testing.T, d *Downloader, stage string, want ethereum.Sync
 	t.Helper()
 
 	p := d.Progress()
-	p.KnownStates, p.PulledStates = 0, 0
+	//p.KnownStates, p.PulledStates = 0, 0
-	want.KnownStates, want.PulledStates = 0, 0
+	//want.KnownStates, want.PulledStates = 0, 0
 	if p != want {
 		t.Fatalf("%s progress mismatch:\nhave %+v\nwant %+v", stage, p, want)
 	}

les/downloader/statesync.go

@@ -22,7 +22,6 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethdb"
@@ -610,6 +609,6 @@ func (s *stateSync) updateStats(written, duplicate, unexpected int, duration tim
 		log.Info("Imported new state entries", "count", written, "elapsed", common.PrettyDuration(duration), "processed", s.d.syncStatsState.processed, "pending", s.d.syncStatsState.pending, "trieretry", len(s.trieTasks), "coderetry", len(s.codeTasks), "duplicate", s.d.syncStatsState.duplicate, "unexpected", s.d.syncStatsState.unexpected)
 	}
 	if written > 0 {
-		rawdb.WriteFastTrieProgress(s.d.stateDB, s.d.syncStatsState.processed)
+		//rawdb.WriteFastTrieProgress(s.d.stateDB, s.d.syncStatsState.processed)
 	}
 }

les/fetcher/block_fetcher_test.go

@@ -60,8 +60,8 @@ func makeChain(n int, seed byte, parent *types.Block) ([]common.Hash, map[common
 			block.AddTx(tx)
 		}
 		// If the block number is a multiple of 5, add a bonus uncle to the block
-		if i%5 == 0 {
+		if i > 0 && i%5 == 0 {
-			block.AddUncle(&types.Header{ParentHash: block.PrevBlock(i - 1).Hash(), Number: big.NewInt(int64(i - 1))})
+			block.AddUncle(&types.Header{ParentHash: block.PrevBlock(i - 2).Hash(), Number: big.NewInt(int64(i - 1))})
 		}
 	})
 	hashes := make([]common.Hash, n+1)

mobile/ethereum.go

@@ -81,8 +81,18 @@ type SyncProgress struct {
 func (p *SyncProgress) GetStartingBlock() int64       { return int64(p.progress.StartingBlock) }
 func (p *SyncProgress) GetCurrentBlock() int64        { return int64(p.progress.CurrentBlock) }
 func (p *SyncProgress) GetHighestBlock() int64        { return int64(p.progress.HighestBlock) }
-func (p *SyncProgress) GetPulledStates() int64  { return int64(p.progress.PulledStates) }
+func (p *SyncProgress) GetSyncedAccounts() int64      { return int64(p.progress.SyncedAccounts) }
-func (p *SyncProgress) GetKnownStates() int64   { return int64(p.progress.KnownStates) }
+func (p *SyncProgress) GetSyncedAccountBytes() int64  { return int64(p.progress.SyncedAccountBytes) }
+func (p *SyncProgress) GetSyncedBytecodes() int64     { return int64(p.progress.SyncedBytecodes) }
+func (p *SyncProgress) GetSyncedBytecodeBytes() int64 { return int64(p.progress.SyncedBytecodeBytes) }
+func (p *SyncProgress) GetSyncedStorage() int64       { return int64(p.progress.SyncedStorage) }
+func (p *SyncProgress) GetSyncedStorageBytes() int64  { return int64(p.progress.SyncedStorageBytes) }
+func (p *SyncProgress) GetHealedTrienodes() int64     { return int64(p.progress.HealedTrienodes) }
+func (p *SyncProgress) GetHealedTrienodeBytes() int64 { return int64(p.progress.HealedTrienodeBytes) }
+func (p *SyncProgress) GetHealedBytecodes() int64     { return int64(p.progress.HealedBytecodes) }
+func (p *SyncProgress) GetHealedBytecodeBytes() int64 { return int64(p.progress.HealedBytecodeBytes) }
+func (p *SyncProgress) GetHealingTrienodes() int64    { return int64(p.progress.HealingTrienodes) }
+func (p *SyncProgress) GetHealingBytecode() int64     { return int64(p.progress.HealingBytecode) }
 
 // Topics is a set of topic lists to filter events with.
 type Topics struct{ topics [][]common.Hash }

p2p/peer.go

@@ -121,10 +121,18 @@ type Peer struct {
 
 // NewPeer returns a peer for testing purposes.
 func NewPeer(id enode.ID, name string, caps []Cap) *Peer {
+	// Generate a fake set of local protocols to match as running caps. Almost
+	// no fields needs to be meaningful here as we're only using it to cross-
+	// check with the "remote" caps array.
+	protos := make([]Protocol, len(caps))
+	for i, cap := range caps {
+		protos[i].Name = cap.Name
+		protos[i].Version = cap.Version
+	}
 	pipe, _ := net.Pipe()
 	node := enode.SignNull(new(enr.Record), id)
 	conn := &conn{fd: pipe, transport: nil, node: node, caps: caps, name: name}
-	peer := newPeer(log.Root(), conn, nil)
+	peer := newPeer(log.Root(), conn, protos)
 	close(peer.closed) // ensures Disconnect doesn't block
 	return peer
 }