From a6deb2d994e644300bac43455b1c954976e7382e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?P=C3=A9ter=20Szil=C3=A1gyi?= Date: Wed, 11 Oct 2023 10:50:09 +0300 Subject: [PATCH] eth/fetcher: throttle tx fetches to 128KB responses (#28304) * eth/fetcher: throttle tx fetches to 128KB responses * eth/fetcher: unindent a clause per review request --- eth/fetcher/tx_fetcher.go | 80 +++++++++++++++++++++------------- eth/fetcher/tx_fetcher_test.go | 72 +++++++++++++++++++++++++++--- 2 files changed, 116 insertions(+), 36 deletions(-) diff --git a/eth/fetcher/tx_fetcher.go b/eth/fetcher/tx_fetcher.go index 8bb5d579d..7a958d2d3 100644 --- a/eth/fetcher/tx_fetcher.go +++ b/eth/fetcher/tx_fetcher.go @@ -39,16 +39,22 @@ const ( // can announce in a short time. maxTxAnnounces = 4096 - // maxTxRetrievals is the maximum transaction number can be fetched in one - // request. The rationale to pick 256 is: - // - In eth protocol, the softResponseLimit is 2MB. Nowadays according to - // Etherscan the average transaction size is around 200B, so in theory - // we can include lots of transaction in a single protocol packet. - // - However the maximum size of a single transaction is raised to 128KB, - // so pick a middle value here to ensure we can maximize the efficiency - // of the retrieval and response size overflow won't happen in most cases. + // maxTxRetrievals is the maximum number of transactions that can be fetched + // in one request. The rationale for picking 256 is to have a reasonabe lower + // bound for the transferred data (don't waste RTTs, transfer more meaningful + // batch sizes), but also have an upper bound on the sequentiality to allow + // using our entire peerset for deliveries. + // + // This number also acts as a failsafe against malicious announces which might + // cause us to request more data than we'd expect. maxTxRetrievals = 256 + // maxTxRetrievalSize is the max number of bytes that delivered transactions + // should weigh according to the announcements. The 128KB was chosen to limit + // retrieving a maximum of one blob transaction at a time to minimize hogging + // a connection between two peers. + maxTxRetrievalSize = 128 * 1024 + // maxTxUnderpricedSetSize is the size of the underpriced transaction set that // is used to track recent transactions that have been dropped so we don't // re-request them. @@ -859,25 +865,36 @@ func (f *TxFetcher) scheduleFetches(timer *mclock.Timer, timeout chan struct{}, if len(f.announces[peer]) == 0 { return // continue in the for-each } - hashes := make([]common.Hash, 0, maxTxRetrievals) - f.forEachHash(f.announces[peer], func(hash common.Hash) bool { - if _, ok := f.fetching[hash]; !ok { - // Mark the hash as fetching and stash away possible alternates - f.fetching[hash] = peer + var ( + hashes = make([]common.Hash, 0, maxTxRetrievals) + bytes uint64 + ) + f.forEachAnnounce(f.announces[peer], func(hash common.Hash, meta *txMetadata) bool { + // If the transaction is alcear fetching, skip to the next one + if _, ok := f.fetching[hash]; ok { + return true + } + // Mark the hash as fetching and stash away possible alternates + f.fetching[hash] = peer - if _, ok := f.alternates[hash]; ok { - panic(fmt.Sprintf("alternate tracker already contains fetching item: %v", f.alternates[hash])) - } - f.alternates[hash] = f.announced[hash] - delete(f.announced, hash) + if _, ok := f.alternates[hash]; ok { + panic(fmt.Sprintf("alternate tracker already contains fetching item: %v", f.alternates[hash])) + } + f.alternates[hash] = f.announced[hash] + delete(f.announced, hash) - // Accumulate the hash and stop if the limit was reached - hashes = append(hashes, hash) - if len(hashes) >= maxTxRetrievals { - return false // break in the for-each + // Accumulate the hash and stop if the limit was reached + hashes = append(hashes, hash) + if len(hashes) >= maxTxRetrievals { + return false // break in the for-each + } + if meta != nil { // Only set eth/68 and upwards + bytes += uint64(meta.size) + if bytes >= maxTxRetrievalSize { + return false } } - return true // continue in the for-each + return true // scheduled, try to add more }) // If any hashes were allocated, request them from the peer if len(hashes) > 0 { @@ -922,27 +939,28 @@ func (f *TxFetcher) forEachPeer(peers map[string]struct{}, do func(peer string)) } } -// forEachHash does a range loop over a map of hashes in production, but during -// testing it does a deterministic sorted random to allow reproducing issues. -func (f *TxFetcher) forEachHash(hashes map[common.Hash]*txMetadata, do func(hash common.Hash) bool) { +// forEachAnnounce does a range loop over a map of announcements in production, +// but during testing it does a deterministic sorted random to allow reproducing +// issues. +func (f *TxFetcher) forEachAnnounce(announces map[common.Hash]*txMetadata, do func(hash common.Hash, meta *txMetadata) bool) { // If we're running production, use whatever Go's map gives us if f.rand == nil { - for hash := range hashes { - if !do(hash) { + for hash, meta := range announces { + if !do(hash, meta) { return } } return } // We're running the test suite, make iteration deterministic - list := make([]common.Hash, 0, len(hashes)) - for hash := range hashes { + list := make([]common.Hash, 0, len(announces)) + for hash := range announces { list = append(list, hash) } sortHashes(list) rotateHashes(list, f.rand.Intn(len(list))) for _, hash := range list { - if !do(hash) { + if !do(hash, announces[hash]) { return } } diff --git a/eth/fetcher/tx_fetcher_test.go b/eth/fetcher/tx_fetcher_test.go index 371e7dd31..fbb9ff9dc 100644 --- a/eth/fetcher/tx_fetcher_test.go +++ b/eth/fetcher/tx_fetcher_test.go @@ -27,6 +27,7 @@ import ( "github.com/ethereum/go-ethereum/common/mclock" "github.com/ethereum/go-ethereum/core/txpool" "github.com/ethereum/go-ethereum/core/types" + "github.com/ethereum/go-ethereum/params" ) var ( @@ -993,15 +994,14 @@ func TestTransactionFetcherTimeoutTimerResets(t *testing.T) { }) } -// Tests that if thousands of transactions are announces, only a small +// Tests that if thousands of transactions are announced, only a small // number of them will be requested at a time. func TestTransactionFetcherRateLimiting(t *testing.T) { - // Create a slew of transactions and to announce them + // Create a slew of transactions and announce them var hashes []common.Hash for i := 0; i < maxTxAnnounces; i++ { hashes = append(hashes, common.Hash{byte(i / 256), byte(i % 256)}) } - testTransactionFetcherParallel(t, txFetcherTest{ init: func() *TxFetcher { return NewTxFetcher( @@ -1029,6 +1029,68 @@ func TestTransactionFetcherRateLimiting(t *testing.T) { }) } +// Tests that if huge transactions are announced, only a small number of them will +// be requested at a time, to keep the responses below a resonable level. +func TestTransactionFetcherBandwidthLimiting(t *testing.T) { + testTransactionFetcherParallel(t, txFetcherTest{ + init: func() *TxFetcher { + return NewTxFetcher( + func(common.Hash) bool { return false }, + nil, + func(string, []common.Hash) error { return nil }, + nil, + ) + }, + steps: []interface{}{ + // Announce mid size transactions from A to verify that multiple + // ones can be piled into a single request. + doTxNotify{peer: "A", + hashes: []common.Hash{{0x01}, {0x02}, {0x03}, {0x04}}, + types: []byte{types.LegacyTxType, types.LegacyTxType, types.LegacyTxType, types.LegacyTxType}, + sizes: []uint32{48 * 1024, 48 * 1024, 48 * 1024, 48 * 1024}, + }, + // Announce exactly on the limit transactions to see that only one + // gets requested + doTxNotify{peer: "B", + hashes: []common.Hash{{0x05}, {0x06}}, + types: []byte{types.LegacyTxType, types.LegacyTxType}, + sizes: []uint32{maxTxRetrievalSize, maxTxRetrievalSize}, + }, + // Announce oversized blob transactions to see that overflows are ok + doTxNotify{peer: "C", + hashes: []common.Hash{{0x07}, {0x08}}, + types: []byte{types.BlobTxType, types.BlobTxType}, + sizes: []uint32{params.MaxBlobGasPerBlock, params.MaxBlobGasPerBlock}, + }, + doWait{time: txArriveTimeout, step: true}, + isWaiting(nil), + isScheduledWithMeta{ + tracking: map[string][]announce{ + "A": { + {common.Hash{0x01}, typeptr(types.LegacyTxType), sizeptr(48 * 1024)}, + {common.Hash{0x02}, typeptr(types.LegacyTxType), sizeptr(48 * 1024)}, + {common.Hash{0x03}, typeptr(types.LegacyTxType), sizeptr(48 * 1024)}, + {common.Hash{0x04}, typeptr(types.LegacyTxType), sizeptr(48 * 1024)}, + }, + "B": { + {common.Hash{0x05}, typeptr(types.LegacyTxType), sizeptr(maxTxRetrievalSize)}, + {common.Hash{0x06}, typeptr(types.LegacyTxType), sizeptr(maxTxRetrievalSize)}, + }, + "C": { + {common.Hash{0x07}, typeptr(types.BlobTxType), sizeptr(params.MaxBlobGasPerBlock)}, + {common.Hash{0x08}, typeptr(types.BlobTxType), sizeptr(params.MaxBlobGasPerBlock)}, + }, + }, + fetching: map[string][]common.Hash{ + "A": {{0x02}, {0x03}, {0x04}}, + "B": {{0x06}}, + "C": {{0x08}}, + }, + }, + }, + }) +} + // Tests that then number of transactions a peer is allowed to announce and/or // request at the same time is hard capped. func TestTransactionFetcherDoSProtection(t *testing.T) { @@ -1664,7 +1726,7 @@ func testTransactionFetcher(t *testing.T, tt txFetcherTest) { if (meta == nil && (ann.kind != nil || ann.size != nil)) || (meta != nil && (ann.kind == nil || ann.size == nil)) || (meta != nil && (meta.kind != *ann.kind || meta.size != *ann.size)) { - t.Errorf("step %d, peer %s, hash %x: waitslot metadata mismatch: want %v, have %v/%v", i, peer, ann.hash, meta, ann.kind, ann.size) + t.Errorf("step %d, peer %s, hash %x: waitslot metadata mismatch: want %v, have %v/%v", i, peer, ann.hash, meta, *ann.kind, *ann.size) } } } @@ -1733,7 +1795,7 @@ func testTransactionFetcher(t *testing.T, tt txFetcherTest) { if (meta == nil && (ann.kind != nil || ann.size != nil)) || (meta != nil && (ann.kind == nil || ann.size == nil)) || (meta != nil && (meta.kind != *ann.kind || meta.size != *ann.size)) { - t.Errorf("step %d, peer %s, hash %x: announce metadata mismatch: want %v, have %v/%v", i, peer, ann.hash, meta, ann.kind, ann.size) + t.Errorf("step %d, peer %s, hash %x: announce metadata mismatch: want %v, have %v/%v", i, peer, ann.hash, meta, *ann.kind, *ann.size) } } }