go-ethereum/core/state/snapshot/wipe.go

92 lines
2.8 KiB
Go

// Copyright 2019 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 snapshot
import (
"bytes"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/metrics"
)
// wipeKeyRange deletes a range of keys from the database starting with prefix
// and having a specific total key length. The start and limit is optional for
// specifying a particular key range for deletion.
//
// Origin is included for wiping and limit is excluded if they are specified.
func wipeKeyRange(db ethdb.KeyValueStore, kind string, prefix []byte, origin []byte, limit []byte, keylen int, meter metrics.Meter, report bool) error {
// Batch deletions together to avoid holding an iterator for too long
var (
batch = db.NewBatch()
items int
)
// Iterate over the key-range and delete all of them
start, logged := time.Now(), time.Now()
it := db.NewIterator(prefix, origin)
var stop []byte
if limit != nil {
stop = append(prefix, limit...)
}
for it.Next() {
// Skip any keys with the correct prefix but wrong length (trie nodes)
key := it.Key()
if !bytes.HasPrefix(key, prefix) {
break
}
if len(key) != keylen {
continue
}
if stop != nil && bytes.Compare(key, stop) >= 0 {
break
}
// Delete the key and periodically recreate the batch and iterator
batch.Delete(key)
items++
if items%10000 == 0 {
// Batch too large (or iterator too long lived, flush and recreate)
it.Release()
if err := batch.Write(); err != nil {
return err
}
batch.Reset()
seekPos := key[len(prefix):]
it = db.NewIterator(prefix, seekPos)
if time.Since(logged) > 8*time.Second && report {
log.Info("Deleting state snapshot leftovers", "kind", kind, "wiped", items, "elapsed", common.PrettyDuration(time.Since(start)))
logged = time.Now()
}
}
}
it.Release()
if err := batch.Write(); err != nil {
return err
}
if meter != nil {
meter.Mark(int64(items))
}
if report {
log.Info("Deleted state snapshot leftovers", "kind", kind, "wiped", items, "elapsed", common.PrettyDuration(time.Since(start)))
}
return nil
}