mirror of https://github.com/ethereum/go-ethereum
Péter Szilágyi
6 years ago
parent
0c5f8c078a
commit
006c21efc7
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// Copyright 2018 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package rawdb |
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import ( |
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"errors" |
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"fmt" |
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"math" |
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"sync/atomic" |
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"time" |
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"github.com/ethereum/go-ethereum/common" |
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"github.com/ethereum/go-ethereum/ethdb" |
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"github.com/ethereum/go-ethereum/log" |
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"github.com/ethereum/go-ethereum/metrics" |
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) |
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// errUnknownTable is returned if the user attempts to read from a table that is
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// not tracked by the freezer.
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var errUnknownTable = errors.New("unknown table") |
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const ( |
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// freezerRecheckInterval is the frequency to check the key-value database for
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// chain progression that might permit new blocks to be frozen into immutable
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// storage.
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freezerRecheckInterval = time.Minute |
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// freezerBlockGraduation is the number of confirmations a block must achieve
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// before it becomes elligible for chain freezing. This must exceed any chain
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// reorg depth, since the freezer also deletes all block siblings.
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freezerBlockGraduation = 60000 |
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// freezerBatchLimit is the maximum number of blocks to freeze in one batch
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// before doing an fsync and deleting it from the key-value store.
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freezerBatchLimit = 30000 |
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) |
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// freezer is an memory mapped append-only database to store immutable chain data
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// into flat files:
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//
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// - The append only nature ensures that disk writes are minimized.
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// - The memory mapping ensures we can max out system memory for caching without
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// reserving it for go-ethereum. This would also reduce the memory requirements
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// of Geth, and thus also GC overhead.
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type freezer struct { |
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tables map[string]*freezerTable // Data tables for storing everything
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frozen uint64 // Number of blocks already frozen
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} |
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// newFreezer creates a chain freezer that moves ancient chain data into
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// append-only flat file containers.
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func newFreezer(datadir string, namespace string) (*freezer, error) { |
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// Create the initial freezer object
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var ( |
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readMeter = metrics.NewRegisteredMeter(namespace+"ancient/read", nil) |
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writeMeter = metrics.NewRegisteredMeter(namespace+"ancient/write", nil) |
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) |
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// Open all the supported data tables
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freezer := &freezer{ |
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tables: make(map[string]*freezerTable), |
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} |
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for _, name := range []string{"hashes", "headers", "bodies", "receipts", "diffs"} { |
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table, err := newTable(datadir, name, readMeter, writeMeter) |
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if err != nil { |
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for _, table := range freezer.tables { |
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table.Close() |
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} |
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return nil, err |
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} |
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freezer.tables[name] = table |
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} |
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// Truncate all data tables to the same length
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freezer.frozen = math.MaxUint64 |
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for _, table := range freezer.tables { |
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if freezer.frozen > table.items { |
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freezer.frozen = table.items |
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} |
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} |
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for _, table := range freezer.tables { |
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if err := table.truncate(freezer.frozen); err != nil { |
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for _, table := range freezer.tables { |
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table.Close() |
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} |
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return nil, err |
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} |
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} |
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return freezer, nil |
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} |
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// Close terminates the chain freezer, unmapping all the data files.
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func (f *freezer) Close() error { |
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var errs []error |
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for _, table := range f.tables { |
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if err := table.Close(); err != nil { |
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errs = append(errs, err) |
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} |
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} |
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if errs != nil { |
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return fmt.Errorf("%v", errs) |
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} |
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return nil |
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} |
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// sync flushes all data tables to disk.
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func (f *freezer) sync() error { |
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var errs []error |
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for _, table := range f.tables { |
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if err := table.Sync(); err != nil { |
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errs = append(errs, err) |
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} |
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} |
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if errs != nil { |
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return fmt.Errorf("%v", errs) |
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} |
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return nil |
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} |
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// Ancient retrieves an ancient binary blob from the append-only immutable files.
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func (f *freezer) Ancient(kind string, number uint64) ([]byte, error) { |
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if table := f.tables[kind]; table != nil { |
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return table.Retrieve(number) |
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} |
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return nil, errUnknownTable |
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} |
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// freeze is a background thread that periodically checks the blockchain for any
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// import progress and moves ancient data from the fast database into the freezer.
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//
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// This functionality is deliberately broken off from block importing to avoid
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// incurring additional data shuffling delays on block propagation.
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func (f *freezer) freeze(db ethdb.KeyValueStore) { |
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nfdb := &nofreezedb{KeyValueStore: db} |
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for { |
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// Retrieve the freezing threshold. In theory we're interested only in full
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// blocks post-sync, but that would keep the live database enormous during
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// dast sync. By picking the fast block, we still get to deep freeze all the
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// final immutable data without having to wait for sync to finish.
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hash := ReadHeadFastBlockHash(nfdb) |
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if hash == (common.Hash{}) { |
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log.Debug("Current fast block hash unavailable") // new chain, empty database
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time.Sleep(freezerRecheckInterval) |
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continue |
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} |
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number := ReadHeaderNumber(nfdb, hash) |
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switch { |
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case number == nil: |
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log.Error("Current fast block number unavailable", "hash", hash) |
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time.Sleep(freezerRecheckInterval) |
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continue |
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case *number < freezerBlockGraduation: |
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log.Debug("Current fast block not old enough", "number", *number, "hash", hash, "delay", freezerBlockGraduation) |
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time.Sleep(freezerRecheckInterval) |
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continue |
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case *number-freezerBlockGraduation <= f.frozen: |
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log.Debug("Ancient blocks frozen already", "number", *number, "hash", hash, "frozen", f.frozen) |
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time.Sleep(freezerRecheckInterval) |
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continue |
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} |
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head := ReadHeader(nfdb, hash, *number) |
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if head == nil { |
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log.Error("Current fast block unavailable", "number", *number, "hash", hash) |
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time.Sleep(freezerRecheckInterval) |
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continue |
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} |
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// Seems we have data ready to be frozen, process in usable batches
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limit := *number - freezerBlockGraduation |
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if limit-f.frozen > freezerBatchLimit { |
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limit = f.frozen + freezerBatchLimit |
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} |
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var ( |
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start = time.Now() |
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first = f.frozen |
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ancients = make([]common.Hash, 0, limit) |
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) |
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for f.frozen < limit { |
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// Retrieves all the components of the canonical block
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hash := ReadCanonicalHash(nfdb, f.frozen) |
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if hash == (common.Hash{}) { |
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log.Error("Canonical hash missing, can't freeze", "number", f.frozen) |
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break |
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} |
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header := ReadHeaderRLP(nfdb, hash, f.frozen) |
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if len(header) == 0 { |
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log.Error("Block header missing, can't freeze", "number", f.frozen, "hash", hash) |
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break |
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} |
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body := ReadBodyRLP(nfdb, hash, f.frozen) |
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if len(body) == 0 { |
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log.Error("Block body missing, can't freeze", "number", f.frozen, "hash", hash) |
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break |
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} |
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receipts := ReadReceiptsRLP(nfdb, hash, f.frozen) |
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if len(receipts) == 0 { |
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log.Error("Block receipts missing, can't freeze", "number", f.frozen, "hash", hash) |
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break |
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} |
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td := ReadTdRLP(nfdb, hash, f.frozen) |
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if len(td) == 0 { |
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log.Error("Total difficulty missing, can't freeze", "number", f.frozen, "hash", hash) |
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break |
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} |
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// Inject all the components into the relevant data tables
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if err := f.tables["hashes"].Append(f.frozen, hash[:]); err != nil { |
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log.Error("Failed to deep freeze hash", "number", f.frozen, "hash", hash, "err", err) |
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break |
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} |
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if err := f.tables["headers"].Append(f.frozen, header); err != nil { |
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log.Error("Failed to deep freeze header", "number", f.frozen, "hash", hash, "err", err) |
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break |
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} |
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if err := f.tables["bodies"].Append(f.frozen, body); err != nil { |
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log.Error("Failed to deep freeze body", "number", f.frozen, "hash", hash, "err", err) |
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break |
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} |
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if err := f.tables["receipts"].Append(f.frozen, receipts); err != nil { |
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log.Error("Failed to deep freeze receipts", "number", f.frozen, "hash", hash, "err", err) |
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break |
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} |
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if err := f.tables["diffs"].Append(f.frozen, td); err != nil { |
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log.Error("Failed to deep freeze difficulty", "number", f.frozen, "hash", hash, "err", err) |
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break |
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} |
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log.Trace("Deep froze ancient block", "number", f.frozen, "hash", hash) |
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atomic.AddUint64(&f.frozen, 1) // Only modify atomically
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ancients = append(ancients, hash) |
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} |
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// Batch of blocks have been frozen, flush them before wiping from leveldb
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if err := f.sync(); err != nil { |
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log.Crit("Failed to flush frozen tables", "err", err) |
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} |
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// Wipe out all data from the active database
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batch := db.NewBatch() |
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for number := first; number < f.frozen; number++ { |
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for _, hash := range readAllHashes(db, number) { |
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if hash == ancients[number-first] { |
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deleteBlockWithoutNumber(batch, hash, number) |
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} else { |
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DeleteBlock(batch, hash, number) |
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} |
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} |
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} |
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if err := batch.Write(); err != nil { |
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log.Crit("Failed to delete frozen items", "err", err) |
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} |
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// Log something friendly for the user
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context := []interface{}{ |
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"blocks", f.frozen - first, "elapsed", common.PrettyDuration(time.Since(start)), "number", f.frozen - 1, |
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} |
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if n := len(ancients); n > 0 { |
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context = append(context, []interface{}{"hash", ancients[n-1]}...) |
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} |
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log.Info("Deep froze chain segment", context...) |
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// Avoid database thrashing with tiny writes
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if f.frozen-first < freezerBatchLimit { |
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time.Sleep(freezerRecheckInterval) |
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} |
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} |
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} |
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@ -0,0 +1,284 @@ |
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// Copyright 2018 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package rawdb |
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import ( |
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"encoding/binary" |
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"errors" |
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"fmt" |
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"os" |
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"path/filepath" |
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"sync" |
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"github.com/ethereum/go-ethereum/common" |
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"github.com/ethereum/go-ethereum/log" |
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"github.com/ethereum/go-ethereum/metrics" |
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"github.com/golang/snappy" |
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) |
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var ( |
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// errClosed is returned if an operation attempts to read from or write to the
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// freezer table after it has already been closed.
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errClosed = errors.New("closed") |
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// errOutOfBounds is returned if the item requested is not contained within the
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// freezer table.
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errOutOfBounds = errors.New("out of bounds") |
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) |
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// freezerTable represents a single chained data table within the freezer (e.g. blocks).
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// It consists of a data file (snappy encoded arbitrary data blobs) and an index
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// file (uncompressed 64 bit indices into the data file).
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type freezerTable struct { |
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content *os.File // File descriptor for the data content of the table
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offsets *os.File // File descriptor for the index file of the table
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items uint64 // Number of items stored in the table
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bytes uint64 // Number of content bytes stored in the table
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readMeter metrics.Meter // Meter for measuring the effective amount of data read
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writeMeter metrics.Meter // Meter for measuring the effective amount of data written
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logger log.Logger // Logger with database path and table name ambedded
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lock sync.RWMutex // Mutex protecting the data file descriptors
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} |
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// newTable opens a freezer table, creating the data and index files if they are
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// non existent. Both files are truncated to the shortest common length to ensure
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// they don't go out of sync.
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func newTable(path string, name string, readMeter metrics.Meter, writeMeter metrics.Meter) (*freezerTable, error) { |
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// Ensure the containing directory exists and open the two data files
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if err := os.MkdirAll(path, 0755); err != nil { |
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return nil, err |
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} |
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content, err := os.OpenFile(filepath.Join(path, name+".dat"), os.O_RDWR|os.O_CREATE|os.O_APPEND, 0644) |
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if err != nil { |
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return nil, err |
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} |
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offsets, err := os.OpenFile(filepath.Join(path, name+".idx"), os.O_RDWR|os.O_CREATE|os.O_APPEND, 0644) |
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if err != nil { |
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content.Close() |
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return nil, err |
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} |
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// Create the table and repair any past inconsistency
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tab := &freezerTable{ |
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content: content, |
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offsets: offsets, |
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readMeter: readMeter, |
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writeMeter: writeMeter, |
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logger: log.New("database", path, "table", name), |
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} |
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if err := tab.repair(); err != nil { |
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offsets.Close() |
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content.Close() |
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return nil, err |
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} |
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return tab, nil |
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} |
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// repair cross checks the content and the offsets file and truncates them to
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// be in sync with each other after a potential crash / data loss.
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func (t *freezerTable) repair() error { |
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// Create a temporary offset buffer to init files with and read offsts into
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offset := make([]byte, 8) |
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// If we've just created the files, initialize the offsets with the 0 index
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stat, err := t.offsets.Stat() |
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if err != nil { |
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return err |
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} |
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if stat.Size() == 0 { |
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if _, err := t.offsets.Write(offset); err != nil { |
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return err |
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} |
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} |
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// Ensure the offsets are a multiple of 8 bytes
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if overflow := stat.Size() % 8; overflow != 0 { |
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t.offsets.Truncate(stat.Size() - overflow) // New file can't trigger this path
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} |
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// Retrieve the file sizes and prepare for truncation
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if stat, err = t.offsets.Stat(); err != nil { |
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return err |
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} |
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offsetsSize := stat.Size() |
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if stat, err = t.content.Stat(); err != nil { |
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return err |
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|
} |
||||||
|
contentSize := stat.Size() |
||||||
|
|
||||||
|
// Keep truncating both files until they come in sync
|
||||||
|
t.offsets.ReadAt(offset, offsetsSize-8) |
||||||
|
contentExp := int64(binary.LittleEndian.Uint64(offset)) |
||||||
|
|
||||||
|
for contentExp != contentSize { |
||||||
|
// Truncate the content file to the last offset pointer
|
||||||
|
if contentExp < contentSize { |
||||||
|
t.logger.Warn("Truncating dangling content", "indexed", common.StorageSize(contentExp), "stored", common.StorageSize(contentSize)) |
||||||
|
if err := t.content.Truncate(contentExp); err != nil { |
||||||
|
return err |
||||||
|
} |
||||||
|
contentSize = contentExp |
||||||
|
} |
||||||
|
// Truncate the offsets to point within the content file
|
||||||
|
if contentExp > contentSize { |
||||||
|
t.logger.Warn("Truncating dangling offsets", "indexed", common.StorageSize(contentExp), "stored", common.StorageSize(contentSize)) |
||||||
|
if err := t.offsets.Truncate(offsetsSize - 8); err != nil { |
||||||
|
return err |
||||||
|
} |
||||||
|
offsetsSize -= 8 |
||||||
|
|
||||||
|
t.offsets.ReadAt(offset, offsetsSize-8) |
||||||
|
contentExp = int64(binary.LittleEndian.Uint64(offset)) |
||||||
|
} |
||||||
|
} |
||||||
|
// Ensure all reparation changes have been written to disk
|
||||||
|
if err := t.offsets.Sync(); err != nil { |
||||||
|
return err |
||||||
|
} |
||||||
|
if err := t.content.Sync(); err != nil { |
||||||
|
return err |
||||||
|
} |
||||||
|
// Update the item and byte counters and return
|
||||||
|
t.items = uint64(offsetsSize/8 - 1) // last index points to the end of the data file
|
||||||
|
t.bytes = uint64(contentSize) |
||||||
|
|
||||||
|
t.logger.Debug("Chain freezer table opened", "items", t.items, "size", common.StorageSize(t.bytes)) |
||||||
|
return nil |
||||||
|
} |
||||||
|
|
||||||
|
// truncate discards any recent data above the provided threashold number.
|
||||||
|
func (t *freezerTable) truncate(items uint64) error { |
||||||
|
// If out item count is corrent, don't do anything
|
||||||
|
if t.items <= items { |
||||||
|
return nil |
||||||
|
} |
||||||
|
// Something's out of sync, truncate the table's offset index
|
||||||
|
t.logger.Warn("Truncating freezer table", "items", t.items, "limit", items) |
||||||
|
if err := t.offsets.Truncate(int64(items+1) * 8); err != nil { |
||||||
|
return err |
||||||
|
} |
||||||
|
// Calculate the new expected size of the data file and truncate it
|
||||||
|
offset := make([]byte, 8) |
||||||
|
t.offsets.ReadAt(offset, int64(items)*8) |
||||||
|
expected := binary.LittleEndian.Uint64(offset) |
||||||
|
|
||||||
|
if err := t.content.Truncate(int64(expected)); err != nil { |
||||||
|
return err |
||||||
|
} |
||||||
|
// All data files truncated, set internal counters and return
|
||||||
|
t.items, t.bytes = items, expected |
||||||
|
return nil |
||||||
|
} |
||||||
|
|
||||||
|
// Close unmaps all active memory mapped regions.
|
||||||
|
func (t *freezerTable) Close() error { |
||||||
|
t.lock.Lock() |
||||||
|
defer t.lock.Unlock() |
||||||
|
|
||||||
|
var errs []error |
||||||
|
if err := t.offsets.Close(); err != nil { |
||||||
|
errs = append(errs, err) |
||||||
|
} |
||||||
|
t.offsets = nil |
||||||
|
|
||||||
|
if err := t.content.Close(); err != nil { |
||||||
|
errs = append(errs, err) |
||||||
|
} |
||||||
|
t.content = nil |
||||||
|
|
||||||
|
if errs != nil { |
||||||
|
return fmt.Errorf("%v", errs) |
||||||
|
} |
||||||
|
return nil |
||||||
|
} |
||||||
|
|
||||||
|
// Append injects a binary blob at the end of the freezer table. The item index
|
||||||
|
// is a precautionary parameter to ensure data correctness, but the table will
|
||||||
|
// reject already existing data.
|
||||||
|
//
|
||||||
|
// Note, this method will *not* flush any data to disk so be sure to explicitly
|
||||||
|
// fsync before irreversibly deleting data from the database.
|
||||||
|
func (t *freezerTable) Append(item uint64, blob []byte) error { |
||||||
|
// Ensure the table is still accessible
|
||||||
|
if t.offsets == nil || t.content == nil { |
||||||
|
return errClosed |
||||||
|
} |
||||||
|
// Ensure only the next item can be written, nothing else
|
||||||
|
if t.items != item { |
||||||
|
panic(fmt.Sprintf("appending unexpected item: want %d, have %d", t.items, item)) |
||||||
|
} |
||||||
|
// Encode the blob and write it into the data file
|
||||||
|
blob = snappy.Encode(nil, blob) |
||||||
|
if _, err := t.content.Write(blob); err != nil { |
||||||
|
return err |
||||||
|
} |
||||||
|
t.bytes += uint64(len(blob)) |
||||||
|
|
||||||
|
offset := make([]byte, 8) |
||||||
|
binary.LittleEndian.PutUint64(offset, t.bytes) |
||||||
|
if _, err := t.offsets.Write(offset); err != nil { |
||||||
|
return err |
||||||
|
} |
||||||
|
t.items++ |
||||||
|
|
||||||
|
t.writeMeter.Mark(int64(len(blob) + 8)) // 8 = 1 x 8 byte offset
|
||||||
|
return nil |
||||||
|
} |
||||||
|
|
||||||
|
// Retrieve looks up the data offset of an item with the given index and retrieves
|
||||||
|
// the raw binary blob from the data file.
|
||||||
|
func (t *freezerTable) Retrieve(item uint64) ([]byte, error) { |
||||||
|
t.lock.RLock() |
||||||
|
defer t.lock.RUnlock() |
||||||
|
|
||||||
|
// Ensure the table and the item is accessible
|
||||||
|
if t.offsets == nil || t.content == nil { |
||||||
|
return nil, errClosed |
||||||
|
} |
||||||
|
if t.items <= item { |
||||||
|
return nil, errOutOfBounds |
||||||
|
} |
||||||
|
// Item reachable, retrieve the data content boundaries
|
||||||
|
offset := make([]byte, 8) |
||||||
|
if _, err := t.offsets.ReadAt(offset, int64(item*8)); err != nil { |
||||||
|
return nil, err |
||||||
|
} |
||||||
|
start := binary.LittleEndian.Uint64(offset) |
||||||
|
|
||||||
|
if _, err := t.offsets.ReadAt(offset, int64((item+1)*8)); err != nil { |
||||||
|
return nil, err |
||||||
|
} |
||||||
|
end := binary.LittleEndian.Uint64(offset) |
||||||
|
|
||||||
|
// Retrieve the data itself, decompress and return
|
||||||
|
blob := make([]byte, end-start) |
||||||
|
if _, err := t.content.ReadAt(blob, int64(start)); err != nil { |
||||||
|
return nil, err |
||||||
|
} |
||||||
|
t.readMeter.Mark(int64(len(blob) + 16)) // 16 = 2 x 8 byte offset
|
||||||
|
return snappy.Decode(nil, blob) |
||||||
|
} |
||||||
|
|
||||||
|
// Sync pushes any pending data from memory out to disk. This is an expensive
|
||||||
|
// operation, so use it with care.
|
||||||
|
func (t *freezerTable) Sync() error { |
||||||
|
if err := t.offsets.Sync(); err != nil { |
||||||
|
return err |
||||||
|
} |
||||||
|
return t.content.Sync() |
||||||
|
} |
||||||
Loading…
Reference in new issue