// Copyright 2018 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 . package hashdb import ( "errors" "fmt" "reflect" "sync" "time" "github.com/VictoriaMetrics/fastcache" "github.com/ethereum/go-ethereum/common" "github.com/ethereum/go-ethereum/core/rawdb" "github.com/ethereum/go-ethereum/core/types" "github.com/ethereum/go-ethereum/ethdb" "github.com/ethereum/go-ethereum/log" "github.com/ethereum/go-ethereum/metrics" "github.com/ethereum/go-ethereum/rlp" "github.com/ethereum/go-ethereum/trie/trienode" "github.com/ethereum/go-ethereum/trie/triestate" "github.com/ethereum/go-ethereum/triedb/database" ) var ( memcacheCleanHitMeter = metrics.NewRegisteredMeter("hashdb/memcache/clean/hit", nil) memcacheCleanMissMeter = metrics.NewRegisteredMeter("hashdb/memcache/clean/miss", nil) memcacheCleanReadMeter = metrics.NewRegisteredMeter("hashdb/memcache/clean/read", nil) memcacheCleanWriteMeter = metrics.NewRegisteredMeter("hashdb/memcache/clean/write", nil) memcacheDirtyHitMeter = metrics.NewRegisteredMeter("hashdb/memcache/dirty/hit", nil) memcacheDirtyMissMeter = metrics.NewRegisteredMeter("hashdb/memcache/dirty/miss", nil) memcacheDirtyReadMeter = metrics.NewRegisteredMeter("hashdb/memcache/dirty/read", nil) memcacheDirtyWriteMeter = metrics.NewRegisteredMeter("hashdb/memcache/dirty/write", nil) memcacheFlushTimeTimer = metrics.NewRegisteredResettingTimer("hashdb/memcache/flush/time", nil) memcacheFlushNodesMeter = metrics.NewRegisteredMeter("hashdb/memcache/flush/nodes", nil) memcacheFlushBytesMeter = metrics.NewRegisteredMeter("hashdb/memcache/flush/bytes", nil) memcacheGCTimeTimer = metrics.NewRegisteredResettingTimer("hashdb/memcache/gc/time", nil) memcacheGCNodesMeter = metrics.NewRegisteredMeter("hashdb/memcache/gc/nodes", nil) memcacheGCBytesMeter = metrics.NewRegisteredMeter("hashdb/memcache/gc/bytes", nil) memcacheCommitTimeTimer = metrics.NewRegisteredResettingTimer("hashdb/memcache/commit/time", nil) memcacheCommitNodesMeter = metrics.NewRegisteredMeter("hashdb/memcache/commit/nodes", nil) memcacheCommitBytesMeter = metrics.NewRegisteredMeter("hashdb/memcache/commit/bytes", nil) ) // ChildResolver defines the required method to decode the provided // trie node and iterate the children on top. type ChildResolver interface { ForEach(node []byte, onChild func(common.Hash)) } // Config contains the settings for database. type Config struct { CleanCacheSize int // Maximum memory allowance (in bytes) for caching clean nodes } // Defaults is the default setting for database if it's not specified. // Notably, clean cache is disabled explicitly, var Defaults = &Config{ // Explicitly set clean cache size to 0 to avoid creating fastcache, // otherwise database must be closed when it's no longer needed to // prevent memory leak. CleanCacheSize: 0, } // Database is an intermediate write layer between the trie data structures and // the disk database. The aim is to accumulate trie writes in-memory and only // periodically flush a couple tries to disk, garbage collecting the remainder. type Database struct { diskdb ethdb.Database // Persistent storage for matured trie nodes resolver ChildResolver // The handler to resolve children of nodes cleans *fastcache.Cache // GC friendly memory cache of clean node RLPs dirties map[common.Hash]*cachedNode // Data and references relationships of dirty trie nodes oldest common.Hash // Oldest tracked node, flush-list head newest common.Hash // Newest tracked node, flush-list tail gctime time.Duration // Time spent on garbage collection since last commit gcnodes uint64 // Nodes garbage collected since last commit gcsize common.StorageSize // Data storage garbage collected since last commit flushtime time.Duration // Time spent on data flushing since last commit flushnodes uint64 // Nodes flushed since last commit flushsize common.StorageSize // Data storage flushed since last commit dirtiesSize common.StorageSize // Storage size of the dirty node cache (exc. metadata) childrenSize common.StorageSize // Storage size of the external children tracking lock sync.RWMutex } // cachedNode is all the information we know about a single cached trie node // in the memory database write layer. type cachedNode struct { node []byte // Encoded node blob, immutable parents uint32 // Number of live nodes referencing this one external map[common.Hash]struct{} // The set of external children flushPrev common.Hash // Previous node in the flush-list flushNext common.Hash // Next node in the flush-list } // cachedNodeSize is the raw size of a cachedNode data structure without any // node data included. It's an approximate size, but should be a lot better // than not counting them. var cachedNodeSize = int(reflect.TypeOf(cachedNode{}).Size()) // forChildren invokes the callback for all the tracked children of this node, // both the implicit ones from inside the node as well as the explicit ones // from outside the node. func (n *cachedNode) forChildren(resolver ChildResolver, onChild func(hash common.Hash)) { for child := range n.external { onChild(child) } resolver.ForEach(n.node, onChild) } // New initializes the hash-based node database. func New(diskdb ethdb.Database, config *Config, resolver ChildResolver) *Database { if config == nil { config = Defaults } var cleans *fastcache.Cache if config.CleanCacheSize > 0 { cleans = fastcache.New(config.CleanCacheSize) } return &Database{ diskdb: diskdb, resolver: resolver, cleans: cleans, dirties: make(map[common.Hash]*cachedNode), } } // insert inserts a trie node into the memory database. All nodes inserted by // this function will be reference tracked. This function assumes the lock is // already held. func (db *Database) insert(hash common.Hash, node []byte) { // If the node's already cached, skip if _, ok := db.dirties[hash]; ok { return } memcacheDirtyWriteMeter.Mark(int64(len(node))) // Create the cached entry for this node entry := &cachedNode{ node: node, flushPrev: db.newest, } entry.forChildren(db.resolver, func(child common.Hash) { if c := db.dirties[child]; c != nil { c.parents++ } }) db.dirties[hash] = entry // Update the flush-list endpoints if db.oldest == (common.Hash{}) { db.oldest, db.newest = hash, hash } else { db.dirties[db.newest].flushNext, db.newest = hash, hash } db.dirtiesSize += common.StorageSize(common.HashLength + len(node)) } // node retrieves an encoded cached trie node from memory. If it cannot be found // cached, the method queries the persistent database for the content. func (db *Database) node(hash common.Hash) ([]byte, error) { // It doesn't make sense to retrieve the metaroot if hash == (common.Hash{}) { return nil, errors.New("not found") } // Retrieve the node from the clean cache if available if db.cleans != nil { if enc := db.cleans.Get(nil, hash[:]); enc != nil { memcacheCleanHitMeter.Mark(1) memcacheCleanReadMeter.Mark(int64(len(enc))) return enc, nil } } // Retrieve the node from the dirty cache if available. db.lock.RLock() dirty := db.dirties[hash] db.lock.RUnlock() // Return the cached node if it's found in the dirty set. // The dirty.node field is immutable and safe to read it // even without lock guard. if dirty != nil { memcacheDirtyHitMeter.Mark(1) memcacheDirtyReadMeter.Mark(int64(len(dirty.node))) return dirty.node, nil } memcacheDirtyMissMeter.Mark(1) // Content unavailable in memory, attempt to retrieve from disk enc := rawdb.ReadLegacyTrieNode(db.diskdb, hash) if len(enc) != 0 { if db.cleans != nil { db.cleans.Set(hash[:], enc) memcacheCleanMissMeter.Mark(1) memcacheCleanWriteMeter.Mark(int64(len(enc))) } return enc, nil } return nil, errors.New("not found") } // Reference adds a new reference from a parent node to a child node. // This function is used to add reference between internal trie node // and external node(e.g. storage trie root), all internal trie nodes // are referenced together by database itself. func (db *Database) Reference(child common.Hash, parent common.Hash) { db.lock.Lock() defer db.lock.Unlock() db.reference(child, parent) } // reference is the private locked version of Reference. func (db *Database) reference(child common.Hash, parent common.Hash) { // If the node does not exist, it's a node pulled from disk, skip node, ok := db.dirties[child] if !ok { return } // The reference is for state root, increase the reference counter. if parent == (common.Hash{}) { node.parents += 1 return } // The reference is for external storage trie, don't duplicate if // the reference is already existent. if db.dirties[parent].external == nil { db.dirties[parent].external = make(map[common.Hash]struct{}) } if _, ok := db.dirties[parent].external[child]; ok { return } node.parents++ db.dirties[parent].external[child] = struct{}{} db.childrenSize += common.HashLength } // Dereference removes an existing reference from a root node. func (db *Database) Dereference(root common.Hash) { // Sanity check to ensure that the meta-root is not removed if root == (common.Hash{}) { log.Error("Attempted to dereference the trie cache meta root") return } db.lock.Lock() defer db.lock.Unlock() nodes, storage, start := len(db.dirties), db.dirtiesSize, time.Now() db.dereference(root) db.gcnodes += uint64(nodes - len(db.dirties)) db.gcsize += storage - db.dirtiesSize db.gctime += time.Since(start) memcacheGCTimeTimer.Update(time.Since(start)) memcacheGCBytesMeter.Mark(int64(storage - db.dirtiesSize)) memcacheGCNodesMeter.Mark(int64(nodes - len(db.dirties))) log.Debug("Dereferenced trie from memory database", "nodes", nodes-len(db.dirties), "size", storage-db.dirtiesSize, "time", time.Since(start), "gcnodes", db.gcnodes, "gcsize", db.gcsize, "gctime", db.gctime, "livenodes", len(db.dirties), "livesize", db.dirtiesSize) } // dereference is the private locked version of Dereference. func (db *Database) dereference(hash common.Hash) { // If the node does not exist, it's a previously committed node. node, ok := db.dirties[hash] if !ok { return } // If there are no more references to the node, delete it and cascade if node.parents > 0 { // This is a special cornercase where a node loaded from disk (i.e. not in the // memcache any more) gets reinjected as a new node (short node split into full, // then reverted into short), causing a cached node to have no parents. That is // no problem in itself, but don't make maxint parents out of it. node.parents-- } if node.parents == 0 { // Remove the node from the flush-list switch hash { case db.oldest: db.oldest = node.flushNext if node.flushNext != (common.Hash{}) { db.dirties[node.flushNext].flushPrev = common.Hash{} } case db.newest: db.newest = node.flushPrev if node.flushPrev != (common.Hash{}) { db.dirties[node.flushPrev].flushNext = common.Hash{} } default: db.dirties[node.flushPrev].flushNext = node.flushNext db.dirties[node.flushNext].flushPrev = node.flushPrev } // Dereference all children and delete the node node.forChildren(db.resolver, func(child common.Hash) { db.dereference(child) }) delete(db.dirties, hash) db.dirtiesSize -= common.StorageSize(common.HashLength + len(node.node)) if node.external != nil { db.childrenSize -= common.StorageSize(len(node.external) * common.HashLength) } } } // Cap iteratively flushes old but still referenced trie nodes until the total // memory usage goes below the given threshold. func (db *Database) Cap(limit common.StorageSize) error { db.lock.Lock() defer db.lock.Unlock() // Create a database batch to flush persistent data out. It is important that // outside code doesn't see an inconsistent state (referenced data removed from // memory cache during commit but not yet in persistent storage). This is ensured // by only uncaching existing data when the database write finalizes. batch := db.diskdb.NewBatch() nodes, storage, start := len(db.dirties), db.dirtiesSize, time.Now() // db.dirtiesSize only contains the useful data in the cache, but when reporting // the total memory consumption, the maintenance metadata is also needed to be // counted. size := db.dirtiesSize + common.StorageSize(len(db.dirties)*cachedNodeSize) size += db.childrenSize // Keep committing nodes from the flush-list until we're below allowance oldest := db.oldest for size > limit && oldest != (common.Hash{}) { // Fetch the oldest referenced node and push into the batch node := db.dirties[oldest] rawdb.WriteLegacyTrieNode(batch, oldest, node.node) // If we exceeded the ideal batch size, commit and reset if batch.ValueSize() >= ethdb.IdealBatchSize { if err := batch.Write(); err != nil { log.Error("Failed to write flush list to disk", "err", err) return err } batch.Reset() } // Iterate to the next flush item, or abort if the size cap was achieved. Size // is the total size, including the useful cached data (hash -> blob), the // cache item metadata, as well as external children mappings. size -= common.StorageSize(common.HashLength + len(node.node) + cachedNodeSize) if node.external != nil { size -= common.StorageSize(len(node.external) * common.HashLength) } oldest = node.flushNext } // Flush out any remainder data from the last batch if err := batch.Write(); err != nil { log.Error("Failed to write flush list to disk", "err", err) return err } // Write successful, clear out the flushed data for db.oldest != oldest { node := db.dirties[db.oldest] delete(db.dirties, db.oldest) db.oldest = node.flushNext db.dirtiesSize -= common.StorageSize(common.HashLength + len(node.node)) if node.external != nil { db.childrenSize -= common.StorageSize(len(node.external) * common.HashLength) } } if db.oldest != (common.Hash{}) { db.dirties[db.oldest].flushPrev = common.Hash{} } db.flushnodes += uint64(nodes - len(db.dirties)) db.flushsize += storage - db.dirtiesSize db.flushtime += time.Since(start) memcacheFlushTimeTimer.Update(time.Since(start)) memcacheFlushBytesMeter.Mark(int64(storage - db.dirtiesSize)) memcacheFlushNodesMeter.Mark(int64(nodes - len(db.dirties))) log.Debug("Persisted nodes from memory database", "nodes", nodes-len(db.dirties), "size", storage-db.dirtiesSize, "time", time.Since(start), "flushnodes", db.flushnodes, "flushsize", db.flushsize, "flushtime", db.flushtime, "livenodes", len(db.dirties), "livesize", db.dirtiesSize) return nil } // Commit iterates over all the children of a particular node, writes them out // to disk, forcefully tearing down all references in both directions. As a side // effect, all pre-images accumulated up to this point are also written. func (db *Database) Commit(node common.Hash, report bool) error { db.lock.Lock() defer db.lock.Unlock() // Create a database batch to flush persistent data out. It is important that // outside code doesn't see an inconsistent state (referenced data removed from // memory cache during commit but not yet in persistent storage). This is ensured // by only uncaching existing data when the database write finalizes. start := time.Now() batch := db.diskdb.NewBatch() // Move the trie itself into the batch, flushing if enough data is accumulated nodes, storage := len(db.dirties), db.dirtiesSize uncacher := &cleaner{db} if err := db.commit(node, batch, uncacher); err != nil { log.Error("Failed to commit trie from trie database", "err", err) return err } // Trie mostly committed to disk, flush any batch leftovers if err := batch.Write(); err != nil { log.Error("Failed to write trie to disk", "err", err) return err } // Uncache any leftovers in the last batch if err := batch.Replay(uncacher); err != nil { return err } batch.Reset() // Reset the storage counters and bumped metrics memcacheCommitTimeTimer.Update(time.Since(start)) memcacheCommitBytesMeter.Mark(int64(storage - db.dirtiesSize)) memcacheCommitNodesMeter.Mark(int64(nodes - len(db.dirties))) logger := log.Info if !report { logger = log.Debug } logger("Persisted trie from memory database", "nodes", nodes-len(db.dirties)+int(db.flushnodes), "size", storage-db.dirtiesSize+db.flushsize, "time", time.Since(start)+db.flushtime, "gcnodes", db.gcnodes, "gcsize", db.gcsize, "gctime", db.gctime, "livenodes", len(db.dirties), "livesize", db.dirtiesSize) // Reset the garbage collection statistics db.gcnodes, db.gcsize, db.gctime = 0, 0, 0 db.flushnodes, db.flushsize, db.flushtime = 0, 0, 0 return nil } // commit is the private locked version of Commit. func (db *Database) commit(hash common.Hash, batch ethdb.Batch, uncacher *cleaner) error { // If the node does not exist, it's a previously committed node node, ok := db.dirties[hash] if !ok { return nil } var err error // Dereference all children and delete the node node.forChildren(db.resolver, func(child common.Hash) { if err == nil { err = db.commit(child, batch, uncacher) } }) if err != nil { return err } // If we've reached an optimal batch size, commit and start over rawdb.WriteLegacyTrieNode(batch, hash, node.node) if batch.ValueSize() >= ethdb.IdealBatchSize { if err := batch.Write(); err != nil { return err } err := batch.Replay(uncacher) if err != nil { return err } batch.Reset() } return nil } // cleaner is a database batch replayer that takes a batch of write operations // and cleans up the trie database from anything written to disk. type cleaner struct { db *Database } // Put reacts to database writes and implements dirty data uncaching. This is the // post-processing step of a commit operation where the already persisted trie is // removed from the dirty cache and moved into the clean cache. The reason behind // the two-phase commit is to ensure data availability while moving from memory // to disk. func (c *cleaner) Put(key []byte, rlp []byte) error { hash := common.BytesToHash(key) // If the node does not exist, we're done on this path node, ok := c.db.dirties[hash] if !ok { return nil } // Node still exists, remove it from the flush-list switch hash { case c.db.oldest: c.db.oldest = node.flushNext if node.flushNext != (common.Hash{}) { c.db.dirties[node.flushNext].flushPrev = common.Hash{} } case c.db.newest: c.db.newest = node.flushPrev if node.flushPrev != (common.Hash{}) { c.db.dirties[node.flushPrev].flushNext = common.Hash{} } default: c.db.dirties[node.flushPrev].flushNext = node.flushNext c.db.dirties[node.flushNext].flushPrev = node.flushPrev } // Remove the node from the dirty cache delete(c.db.dirties, hash) c.db.dirtiesSize -= common.StorageSize(common.HashLength + len(node.node)) if node.external != nil { c.db.childrenSize -= common.StorageSize(len(node.external) * common.HashLength) } // Move the flushed node into the clean cache to prevent insta-reloads if c.db.cleans != nil { c.db.cleans.Set(hash[:], rlp) memcacheCleanWriteMeter.Mark(int64(len(rlp))) } return nil } func (c *cleaner) Delete(key []byte) error { panic("not implemented") } // Initialized returns an indicator if state data is already initialized // in hash-based scheme by checking the presence of genesis state. func (db *Database) Initialized(genesisRoot common.Hash) bool { return rawdb.HasLegacyTrieNode(db.diskdb, genesisRoot) } // Update inserts the dirty nodes in provided nodeset into database and link the // account trie with multiple storage tries if necessary. func (db *Database) Update(root common.Hash, parent common.Hash, block uint64, nodes *trienode.MergedNodeSet, states *triestate.Set) error { // Ensure the parent state is present and signal a warning if not. if parent != types.EmptyRootHash { if blob, _ := db.node(parent); len(blob) == 0 { log.Error("parent state is not present") } } db.lock.Lock() defer db.lock.Unlock() // Insert dirty nodes into the database. In the same tree, it must be // ensured that children are inserted first, then parent so that children // can be linked with their parent correctly. // // Note, the storage tries must be flushed before the account trie to // retain the invariant that children go into the dirty cache first. var order []common.Hash for owner := range nodes.Sets { if owner == (common.Hash{}) { continue } order = append(order, owner) } if _, ok := nodes.Sets[common.Hash{}]; ok { order = append(order, common.Hash{}) } for _, owner := range order { subset := nodes.Sets[owner] subset.ForEachWithOrder(func(path string, n *trienode.Node) { if n.IsDeleted() { return // ignore deletion } db.insert(n.Hash, n.Blob) }) } // Link up the account trie and storage trie if the node points // to an account trie leaf. if set, present := nodes.Sets[common.Hash{}]; present { for _, n := range set.Leaves { var account types.StateAccount if err := rlp.DecodeBytes(n.Blob, &account); err != nil { return err } if account.Root != types.EmptyRootHash { db.reference(account.Root, n.Parent) } } } return nil } // Size returns the current storage size of the memory cache in front of the // persistent database layer. // // The first return will always be 0, representing the memory stored in unbounded // diff layers above the dirty cache. This is only available in pathdb. func (db *Database) Size() (common.StorageSize, common.StorageSize) { db.lock.RLock() defer db.lock.RUnlock() // db.dirtiesSize only contains the useful data in the cache, but when reporting // the total memory consumption, the maintenance metadata is also needed to be // counted. var metadataSize = common.StorageSize(len(db.dirties) * cachedNodeSize) return 0, db.dirtiesSize + db.childrenSize + metadataSize } // Close closes the trie database and releases all held resources. func (db *Database) Close() error { if db.cleans != nil { db.cleans.Reset() } return nil } // Reader retrieves a node reader belonging to the given state root. // An error will be returned if the requested state is not available. func (db *Database) Reader(root common.Hash) (database.Reader, error) { if _, err := db.node(root); err != nil { return nil, fmt.Errorf("state %#x is not available, %v", root, err) } return &reader{db: db}, nil } // reader is a state reader of Database which implements the Reader interface. type reader struct { db *Database } // Node retrieves the trie node with the given node hash. No error will be // returned if the node is not found. func (reader *reader) Node(owner common.Hash, path []byte, hash common.Hash) ([]byte, error) { blob, _ := reader.db.node(hash) return blob, nil }