plugeth/core/rawdb/chain_freezer.go

306 lines
9.7 KiB
Go

// Copyright 2022 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 rawdb
import (
"fmt"
"sync"
"sync/atomic"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/params"
)
const (
// freezerRecheckInterval is the frequency to check the key-value database for
// chain progression that might permit new blocks to be frozen into immutable
// storage.
freezerRecheckInterval = time.Minute
// freezerBatchLimit is the maximum number of blocks to freeze in one batch
// before doing an fsync and deleting it from the key-value store.
freezerBatchLimit = 30000
)
// chainFreezer is a wrapper of freezer with additional chain freezing feature.
// The background thread will keep moving ancient chain segments from key-value
// database to flat files for saving space on live database.
type chainFreezer struct {
// WARNING: The `threshold` field is accessed atomically. On 32 bit platforms, only
// 64-bit aligned fields can be atomic. The struct is guaranteed to be so aligned,
// so take advantage of that (https://golang.org/pkg/sync/atomic/#pkg-note-BUG).
threshold uint64 // Number of recent blocks not to freeze (params.FullImmutabilityThreshold apart from tests)
*Freezer
quit chan struct{}
wg sync.WaitGroup
trigger chan chan struct{} // Manual blocking freeze trigger, test determinism
}
// newChainFreezer initializes the freezer for ancient chain data.
func newChainFreezer(datadir string, namespace string, readonly bool) (*chainFreezer, error) {
freezer, err := NewChainFreezer(datadir, namespace, readonly)
if err != nil {
return nil, err
}
return &chainFreezer{
Freezer: freezer,
threshold: params.FullImmutabilityThreshold,
quit: make(chan struct{}),
trigger: make(chan chan struct{}),
}, nil
}
// Close closes the chain freezer instance and terminates the background thread.
func (f *chainFreezer) Close() error {
select {
case <-f.quit:
default:
close(f.quit)
}
f.wg.Wait()
return f.Freezer.Close()
}
// freeze is a background thread that periodically checks the blockchain for any
// import progress and moves ancient data from the fast database into the freezer.
//
// This functionality is deliberately broken off from block importing to avoid
// incurring additional data shuffling delays on block propagation.
func (f *chainFreezer) freeze(db ethdb.KeyValueStore) {
var (
backoff bool
triggered chan struct{} // Used in tests
nfdb = &nofreezedb{KeyValueStore: db}
)
timer := time.NewTimer(freezerRecheckInterval)
defer timer.Stop()
for {
select {
case <-f.quit:
log.Info("Freezer shutting down")
return
default:
}
if backoff {
// If we were doing a manual trigger, notify it
if triggered != nil {
triggered <- struct{}{}
triggered = nil
}
select {
case <-timer.C:
backoff = false
timer.Reset(freezerRecheckInterval)
case triggered = <-f.trigger:
backoff = false
case <-f.quit:
return
}
}
// Retrieve the freezing threshold.
hash := ReadHeadBlockHash(nfdb)
if hash == (common.Hash{}) {
log.Debug("Current full block hash unavailable") // new chain, empty database
backoff = true
continue
}
number := ReadHeaderNumber(nfdb, hash)
threshold := atomic.LoadUint64(&f.threshold)
frozen := atomic.LoadUint64(&f.frozen)
switch {
case number == nil:
log.Error("Current full block number unavailable", "hash", hash)
backoff = true
continue
case *number < threshold:
log.Debug("Current full block not old enough", "number", *number, "hash", hash, "delay", threshold)
backoff = true
continue
case *number-threshold <= frozen:
log.Debug("Ancient blocks frozen already", "number", *number, "hash", hash, "frozen", frozen)
backoff = true
continue
}
head := ReadHeader(nfdb, hash, *number)
if head == nil {
log.Error("Current full block unavailable", "number", *number, "hash", hash)
backoff = true
continue
}
// Seems we have data ready to be frozen, process in usable batches
var (
start = time.Now()
first, _ = f.Ancients()
limit = *number - threshold
)
if limit-first > freezerBatchLimit {
limit = first + freezerBatchLimit
}
ancients, err := f.freezeRange(nfdb, first, limit)
if err != nil {
log.Error("Error in block freeze operation", "err", err)
backoff = true
continue
}
// Batch of blocks have been frozen, flush them before wiping from leveldb
if err := f.Sync(); err != nil {
log.Crit("Failed to flush frozen tables", "err", err)
}
// Wipe out all data from the active database
batch := db.NewBatch()
for i := 0; i < len(ancients); i++ {
// Always keep the genesis block in active database
if first+uint64(i) != 0 {
DeleteBlockWithoutNumber(batch, ancients[i], first+uint64(i))
DeleteCanonicalHash(batch, first+uint64(i))
}
}
if err := batch.Write(); err != nil {
log.Crit("Failed to delete frozen canonical blocks", "err", err)
}
batch.Reset()
// Wipe out side chains also and track dangling side chains
var dangling []common.Hash
frozen = atomic.LoadUint64(&f.frozen) // Needs reload after during freezeRange
for number := first; number < frozen; number++ {
// Always keep the genesis block in active database
if number != 0 {
dangling = ReadAllHashes(db, number)
for _, hash := range dangling {
log.Trace("Deleting side chain", "number", number, "hash", hash)
DeleteBlock(batch, hash, number)
}
}
}
if err := batch.Write(); err != nil {
log.Crit("Failed to delete frozen side blocks", "err", err)
}
batch.Reset()
// Step into the future and delete and dangling side chains
if frozen > 0 {
tip := frozen
for len(dangling) > 0 {
drop := make(map[common.Hash]struct{})
for _, hash := range dangling {
log.Debug("Dangling parent from Freezer", "number", tip-1, "hash", hash)
drop[hash] = struct{}{}
}
children := ReadAllHashes(db, tip)
for i := 0; i < len(children); i++ {
// Dig up the child and ensure it's dangling
child := ReadHeader(nfdb, children[i], tip)
if child == nil {
log.Error("Missing dangling header", "number", tip, "hash", children[i])
continue
}
if _, ok := drop[child.ParentHash]; !ok {
children = append(children[:i], children[i+1:]...)
i--
continue
}
// Delete all block data associated with the child
log.Debug("Deleting dangling block", "number", tip, "hash", children[i], "parent", child.ParentHash)
DeleteBlock(batch, children[i], tip)
}
dangling = children
tip++
}
if err := batch.Write(); err != nil {
log.Crit("Failed to delete dangling side blocks", "err", err)
}
}
// Log something friendly for the user
context := []interface{}{
"blocks", frozen - first, "elapsed", common.PrettyDuration(time.Since(start)), "number", frozen - 1,
}
if n := len(ancients); n > 0 {
context = append(context, []interface{}{"hash", ancients[n-1]}...)
}
log.Debug("Deep froze chain segment", context...)
// Avoid database thrashing with tiny writes
if frozen-first < freezerBatchLimit {
backoff = true
}
}
}
func (f *chainFreezer) freezeRange(nfdb *nofreezedb, number, limit uint64) (hashes []common.Hash, err error) {
hashes = make([]common.Hash, 0, limit-number)
_, err = f.ModifyAncients(func(op ethdb.AncientWriteOp) error {
for ; number <= limit; number++ {
// Retrieve all the components of the canonical block.
hash := ReadCanonicalHash(nfdb, number)
if hash == (common.Hash{}) {
return fmt.Errorf("canonical hash missing, can't freeze block %d", number)
}
header := ReadHeaderRLP(nfdb, hash, number)
if len(header) == 0 {
return fmt.Errorf("block header missing, can't freeze block %d", number)
}
body := ReadBodyRLP(nfdb, hash, number)
if len(body) == 0 {
return fmt.Errorf("block body missing, can't freeze block %d", number)
}
receipts := ReadReceiptsRLP(nfdb, hash, number)
if len(receipts) == 0 {
return fmt.Errorf("block receipts missing, can't freeze block %d", number)
}
td := ReadTdRLP(nfdb, hash, number)
if len(td) == 0 {
return fmt.Errorf("total difficulty missing, can't freeze block %d", number)
}
// Write to the batch.
if err := op.AppendRaw(ChainFreezerHashTable, number, hash[:]); err != nil {
return fmt.Errorf("can't write hash to Freezer: %v", err)
}
if err := op.AppendRaw(ChainFreezerHeaderTable, number, header); err != nil {
return fmt.Errorf("can't write header to Freezer: %v", err)
}
if err := op.AppendRaw(ChainFreezerBodiesTable, number, body); err != nil {
return fmt.Errorf("can't write body to Freezer: %v", err)
}
if err := op.AppendRaw(ChainFreezerReceiptTable, number, receipts); err != nil {
return fmt.Errorf("can't write receipts to Freezer: %v", err)
}
if err := op.AppendRaw(ChainFreezerDifficultyTable, number, td); err != nil {
return fmt.Errorf("can't write td to Freezer: %v", err)
}
hashes = append(hashes, hash)
}
return nil
})
return hashes, err
}