github.com/cryptotooltop/go-ethereum@v0.0.0-20231103184714-151d1922f3e5/trie/database.go (about)

     1  // Copyright 2018 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package trie
    18  
    19  import (
    20  	"errors"
    21  	"fmt"
    22  	"io"
    23  	"reflect"
    24  	"runtime"
    25  	"sync"
    26  	"time"
    27  
    28  	"github.com/VictoriaMetrics/fastcache"
    29  
    30  	"github.com/scroll-tech/go-ethereum/common"
    31  	"github.com/scroll-tech/go-ethereum/core/rawdb"
    32  	"github.com/scroll-tech/go-ethereum/ethdb"
    33  	"github.com/scroll-tech/go-ethereum/log"
    34  	"github.com/scroll-tech/go-ethereum/metrics"
    35  	"github.com/scroll-tech/go-ethereum/rlp"
    36  )
    37  
    38  var (
    39  	memcacheCleanHitMeter   = metrics.NewRegisteredMeter("trie/memcache/clean/hit", nil)
    40  	memcacheCleanMissMeter  = metrics.NewRegisteredMeter("trie/memcache/clean/miss", nil)
    41  	memcacheCleanReadMeter  = metrics.NewRegisteredMeter("trie/memcache/clean/read", nil)
    42  	memcacheCleanWriteMeter = metrics.NewRegisteredMeter("trie/memcache/clean/write", nil)
    43  
    44  	memcacheDirtyHitMeter   = metrics.NewRegisteredMeter("trie/memcache/dirty/hit", nil)
    45  	memcacheDirtyMissMeter  = metrics.NewRegisteredMeter("trie/memcache/dirty/miss", nil)
    46  	memcacheDirtyReadMeter  = metrics.NewRegisteredMeter("trie/memcache/dirty/read", nil)
    47  	memcacheDirtyWriteMeter = metrics.NewRegisteredMeter("trie/memcache/dirty/write", nil)
    48  
    49  	memcacheFlushTimeTimer  = metrics.NewRegisteredResettingTimer("trie/memcache/flush/time", nil)
    50  	memcacheFlushNodesMeter = metrics.NewRegisteredMeter("trie/memcache/flush/nodes", nil)
    51  	memcacheFlushSizeMeter  = metrics.NewRegisteredMeter("trie/memcache/flush/size", nil)
    52  
    53  	memcacheGCTimeTimer  = metrics.NewRegisteredResettingTimer("trie/memcache/gc/time", nil)
    54  	memcacheGCNodesMeter = metrics.NewRegisteredMeter("trie/memcache/gc/nodes", nil)
    55  	memcacheGCSizeMeter  = metrics.NewRegisteredMeter("trie/memcache/gc/size", nil)
    56  
    57  	memcacheCommitTimeTimer  = metrics.NewRegisteredResettingTimer("trie/memcache/commit/time", nil)
    58  	memcacheCommitNodesMeter = metrics.NewRegisteredMeter("trie/memcache/commit/nodes", nil)
    59  	memcacheCommitSizeMeter  = metrics.NewRegisteredMeter("trie/memcache/commit/size", nil)
    60  )
    61  
    62  // Database is an intermediate write layer between the trie data structures and
    63  // the disk database. The aim is to accumulate trie writes in-memory and only
    64  // periodically flush a couple tries to disk, garbage collecting the remainder.
    65  //
    66  // Note, the trie Database is **not** thread safe in its mutations, but it **is**
    67  // thread safe in providing individual, independent node access. The rationale
    68  // behind this split design is to provide read access to RPC handlers and sync
    69  // servers even while the trie is executing expensive garbage collection.
    70  type Database struct {
    71  	diskdb ethdb.KeyValueStore // Persistent storage for matured trie nodes
    72  
    73  	// zktrie related stuff
    74  	Zktrie bool
    75  	// TODO: It's a quick&dirty implementation. FIXME later.
    76  	rawDirties KvMap
    77  
    78  	cleans  *fastcache.Cache            // GC friendly memory cache of clean node RLPs
    79  	dirties map[common.Hash]*cachedNode // Data and references relationships of dirty trie nodes
    80  	oldest  common.Hash                 // Oldest tracked node, flush-list head
    81  	newest  common.Hash                 // Newest tracked node, flush-list tail
    82  
    83  	gctime  time.Duration      // Time spent on garbage collection since last commit
    84  	gcnodes uint64             // Nodes garbage collected since last commit
    85  	gcsize  common.StorageSize // Data storage garbage collected since last commit
    86  
    87  	flushtime  time.Duration      // Time spent on data flushing since last commit
    88  	flushnodes uint64             // Nodes flushed since last commit
    89  	flushsize  common.StorageSize // Data storage flushed since last commit
    90  
    91  	dirtiesSize  common.StorageSize // Storage size of the dirty node cache (exc. metadata)
    92  	childrenSize common.StorageSize // Storage size of the external children tracking
    93  	preimages    *preimageStore     // The store for caching preimages
    94  
    95  	lock sync.RWMutex
    96  }
    97  
    98  // rawNode is a simple binary blob used to differentiate between collapsed trie
    99  // nodes and already encoded RLP binary blobs (while at the same time store them
   100  // in the same cache fields).
   101  type rawNode []byte
   102  
   103  func (n rawNode) cache() (hashNode, bool)   { panic("this should never end up in a live trie") }
   104  func (n rawNode) fstring(ind string) string { panic("this should never end up in a live trie") }
   105  
   106  func (n rawNode) EncodeRLP(w io.Writer) error {
   107  	_, err := w.Write(n)
   108  	return err
   109  }
   110  
   111  // rawFullNode represents only the useful data content of a full node, with the
   112  // caches and flags stripped out to minimize its data storage. This type honors
   113  // the same RLP encoding as the original parent.
   114  type rawFullNode [17]node
   115  
   116  func (n rawFullNode) cache() (hashNode, bool)   { panic("this should never end up in a live trie") }
   117  func (n rawFullNode) fstring(ind string) string { panic("this should never end up in a live trie") }
   118  
   119  func (n rawFullNode) EncodeRLP(w io.Writer) error {
   120  	var nodes [17]node
   121  
   122  	for i, child := range n {
   123  		if child != nil {
   124  			nodes[i] = child
   125  		} else {
   126  			nodes[i] = nilValueNode
   127  		}
   128  	}
   129  	return rlp.Encode(w, nodes)
   130  }
   131  
   132  // rawShortNode represents only the useful data content of a short node, with the
   133  // caches and flags stripped out to minimize its data storage. This type honors
   134  // the same RLP encoding as the original parent.
   135  type rawShortNode struct {
   136  	Key []byte
   137  	Val node
   138  }
   139  
   140  func (n rawShortNode) cache() (hashNode, bool)   { panic("this should never end up in a live trie") }
   141  func (n rawShortNode) fstring(ind string) string { panic("this should never end up in a live trie") }
   142  
   143  // cachedNode is all the information we know about a single cached trie node
   144  // in the memory database write layer.
   145  type cachedNode struct {
   146  	node node   // Cached collapsed trie node, or raw rlp data
   147  	size uint16 // Byte size of the useful cached data
   148  
   149  	parents  uint32                 // Number of live nodes referencing this one
   150  	children map[common.Hash]uint16 // External children referenced by this node
   151  
   152  	flushPrev common.Hash // Previous node in the flush-list
   153  	flushNext common.Hash // Next node in the flush-list
   154  }
   155  
   156  // cachedNodeSize is the raw size of a cachedNode data structure without any
   157  // node data included. It's an approximate size, but should be a lot better
   158  // than not counting them.
   159  var cachedNodeSize = int(reflect.TypeOf(cachedNode{}).Size())
   160  
   161  // cachedNodeChildrenSize is the raw size of an initialized but empty external
   162  // reference map.
   163  const cachedNodeChildrenSize = 48
   164  
   165  // rlp returns the raw rlp encoded blob of the cached trie node, either directly
   166  // from the cache, or by regenerating it from the collapsed node.
   167  func (n *cachedNode) rlp() []byte {
   168  	if node, ok := n.node.(rawNode); ok {
   169  		return node
   170  	}
   171  	blob, err := rlp.EncodeToBytes(n.node)
   172  	if err != nil {
   173  		panic(err)
   174  	}
   175  	return blob
   176  }
   177  
   178  // obj returns the decoded and expanded trie node, either directly from the cache,
   179  // or by regenerating it from the rlp encoded blob.
   180  func (n *cachedNode) obj(hash common.Hash) node {
   181  	if node, ok := n.node.(rawNode); ok {
   182  		return mustDecodeNode(hash[:], node)
   183  	}
   184  	return expandNode(hash[:], n.node)
   185  }
   186  
   187  // forChilds invokes the callback for all the tracked children of this node,
   188  // both the implicit ones from inside the node as well as the explicit ones
   189  // from outside the node.
   190  func (n *cachedNode) forChilds(onChild func(hash common.Hash)) {
   191  	for child := range n.children {
   192  		onChild(child)
   193  	}
   194  	if _, ok := n.node.(rawNode); !ok {
   195  		forGatherChildren(n.node, onChild)
   196  	}
   197  }
   198  
   199  // forGatherChildren traverses the node hierarchy of a collapsed storage node and
   200  // invokes the callback for all the hashnode children.
   201  func forGatherChildren(n node, onChild func(hash common.Hash)) {
   202  	switch n := n.(type) {
   203  	case *rawShortNode:
   204  		forGatherChildren(n.Val, onChild)
   205  	case rawFullNode:
   206  		for i := 0; i < 16; i++ {
   207  			forGatherChildren(n[i], onChild)
   208  		}
   209  	case hashNode:
   210  		onChild(common.BytesToHash(n))
   211  	case valueNode, nil, rawNode:
   212  	default:
   213  		panic(fmt.Sprintf("unknown node type: %T", n))
   214  	}
   215  }
   216  
   217  // simplifyNode traverses the hierarchy of an expanded memory node and discards
   218  // all the internal caches, returning a node that only contains the raw data.
   219  func simplifyNode(n node) node {
   220  	switch n := n.(type) {
   221  	case *shortNode:
   222  		// Short nodes discard the flags and cascade
   223  		return &rawShortNode{Key: n.Key, Val: simplifyNode(n.Val)}
   224  
   225  	case *fullNode:
   226  		// Full nodes discard the flags and cascade
   227  		node := rawFullNode(n.Children)
   228  		for i := 0; i < len(node); i++ {
   229  			if node[i] != nil {
   230  				node[i] = simplifyNode(node[i])
   231  			}
   232  		}
   233  		return node
   234  
   235  	case valueNode, hashNode, rawNode:
   236  		return n
   237  
   238  	default:
   239  		panic(fmt.Sprintf("unknown node type: %T", n))
   240  	}
   241  }
   242  
   243  // expandNode traverses the node hierarchy of a collapsed storage node and converts
   244  // all fields and keys into expanded memory form.
   245  func expandNode(hash hashNode, n node) node {
   246  	switch n := n.(type) {
   247  	case *rawShortNode:
   248  		// Short nodes need key and child expansion
   249  		return &shortNode{
   250  			Key: compactToHex(n.Key),
   251  			Val: expandNode(nil, n.Val),
   252  			flags: nodeFlag{
   253  				hash: hash,
   254  			},
   255  		}
   256  
   257  	case rawFullNode:
   258  		// Full nodes need child expansion
   259  		node := &fullNode{
   260  			flags: nodeFlag{
   261  				hash: hash,
   262  			},
   263  		}
   264  		for i := 0; i < len(node.Children); i++ {
   265  			if n[i] != nil {
   266  				node.Children[i] = expandNode(nil, n[i])
   267  			}
   268  		}
   269  		return node
   270  
   271  	case valueNode, hashNode:
   272  		return n
   273  
   274  	default:
   275  		panic(fmt.Sprintf("unknown node type: %T", n))
   276  	}
   277  }
   278  
   279  // Config defines all necessary options for database.
   280  type Config struct {
   281  	Cache     int    // Memory allowance (MB) to use for caching trie nodes in memory
   282  	Journal   string // Journal of clean cache to survive node restarts
   283  	Preimages bool   // Flag whether the preimage of trie key is recorded
   284  	Zktrie    bool   // use zktrie
   285  }
   286  
   287  // NewDatabase creates a new trie database to store ephemeral trie content before
   288  // its written out to disk or garbage collected. No read cache is created, so all
   289  // data retrievals will hit the underlying disk database.
   290  func NewDatabase(diskdb ethdb.KeyValueStore) *Database {
   291  	return NewDatabaseWithConfig(diskdb, nil)
   292  }
   293  
   294  // NewDatabaseWithConfig creates a new trie database to store ephemeral trie content
   295  // before its written out to disk or garbage collected. It also acts as a read cache
   296  // for nodes loaded from disk.
   297  func NewDatabaseWithConfig(diskdb ethdb.KeyValueStore, config *Config) *Database {
   298  	var cleans *fastcache.Cache
   299  	if config != nil && config.Cache > 0 {
   300  		if config.Journal == "" {
   301  			cleans = fastcache.New(config.Cache * 1024 * 1024)
   302  		} else {
   303  			cleans = fastcache.LoadFromFileOrNew(config.Journal, config.Cache*1024*1024)
   304  		}
   305  	}
   306  	var preimage *preimageStore
   307  	if config != nil && config.Preimages {
   308  		preimage = newPreimageStore(diskdb)
   309  	}
   310  	db := &Database{
   311  		diskdb: diskdb,
   312  		cleans: cleans,
   313  		dirties: map[common.Hash]*cachedNode{{}: {
   314  			children: make(map[common.Hash]uint16),
   315  		}},
   316  		rawDirties: make(KvMap),
   317  		preimages:  preimage,
   318  	}
   319  	return db
   320  }
   321  
   322  // DiskDB retrieves the persistent storage backing the trie database.
   323  func (db *Database) DiskDB() ethdb.KeyValueStore {
   324  	return db.diskdb
   325  }
   326  
   327  // insert inserts a collapsed trie node into the memory database.
   328  // The blob size must be specified to allow proper size tracking.
   329  // All nodes inserted by this function will be reference tracked
   330  // and in theory should only used for **trie nodes** insertion.
   331  func (db *Database) insert(hash common.Hash, size int, node node) {
   332  	// If the node's already cached, skip
   333  	if _, ok := db.dirties[hash]; ok {
   334  		return
   335  	}
   336  	memcacheDirtyWriteMeter.Mark(int64(size))
   337  
   338  	// Create the cached entry for this node
   339  	entry := &cachedNode{
   340  		node:      simplifyNode(node),
   341  		size:      uint16(size),
   342  		flushPrev: db.newest,
   343  	}
   344  	entry.forChilds(func(child common.Hash) {
   345  		if c := db.dirties[child]; c != nil {
   346  			c.parents++
   347  		}
   348  	})
   349  	db.dirties[hash] = entry
   350  
   351  	// Update the flush-list endpoints
   352  	if db.oldest == (common.Hash{}) {
   353  		db.oldest, db.newest = hash, hash
   354  	} else {
   355  		db.dirties[db.newest].flushNext, db.newest = hash, hash
   356  	}
   357  	db.dirtiesSize += common.StorageSize(common.HashLength + entry.size)
   358  }
   359  
   360  // node retrieves a cached trie node from memory, or returns nil if none can be
   361  // found in the memory cache.
   362  func (db *Database) node(hash common.Hash) node {
   363  	// Retrieve the node from the clean cache if available
   364  	if db.cleans != nil {
   365  		if enc := db.cleans.Get(nil, hash[:]); enc != nil {
   366  			memcacheCleanHitMeter.Mark(1)
   367  			memcacheCleanReadMeter.Mark(int64(len(enc)))
   368  			return mustDecodeNode(hash[:], enc)
   369  		}
   370  	}
   371  	// Retrieve the node from the dirty cache if available
   372  	db.lock.RLock()
   373  	dirty := db.dirties[hash]
   374  	db.lock.RUnlock()
   375  
   376  	if dirty != nil {
   377  		memcacheDirtyHitMeter.Mark(1)
   378  		memcacheDirtyReadMeter.Mark(int64(dirty.size))
   379  		return dirty.obj(hash)
   380  	}
   381  	memcacheDirtyMissMeter.Mark(1)
   382  
   383  	// Content unavailable in memory, attempt to retrieve from disk
   384  	enc, err := db.diskdb.Get(hash[:])
   385  	if err != nil || enc == nil {
   386  		return nil
   387  	}
   388  	if db.cleans != nil {
   389  		db.cleans.Set(hash[:], enc)
   390  		memcacheCleanMissMeter.Mark(1)
   391  		memcacheCleanWriteMeter.Mark(int64(len(enc)))
   392  	}
   393  	return mustDecodeNode(hash[:], enc)
   394  }
   395  
   396  // Node retrieves an encoded cached trie node from memory. If it cannot be found
   397  // cached, the method queries the persistent database for the content.
   398  func (db *Database) Node(hash common.Hash) ([]byte, error) {
   399  	// It doesn't make sense to retrieve the metaroot
   400  	if hash == (common.Hash{}) {
   401  		return nil, errors.New("not found")
   402  	}
   403  	// Retrieve the node from the clean cache if available
   404  	if db.cleans != nil {
   405  		if enc := db.cleans.Get(nil, hash[:]); enc != nil {
   406  			memcacheCleanHitMeter.Mark(1)
   407  			memcacheCleanReadMeter.Mark(int64(len(enc)))
   408  			return enc, nil
   409  		}
   410  	}
   411  	// Retrieve the node from the dirty cache if available
   412  	db.lock.RLock()
   413  	dirty := db.dirties[hash]
   414  	db.lock.RUnlock()
   415  
   416  	if dirty != nil {
   417  		memcacheDirtyHitMeter.Mark(1)
   418  		memcacheDirtyReadMeter.Mark(int64(dirty.size))
   419  		return dirty.rlp(), nil
   420  	}
   421  	memcacheDirtyMissMeter.Mark(1)
   422  
   423  	// Content unavailable in memory, attempt to retrieve from disk
   424  	enc := rawdb.ReadTrieNode(db.diskdb, hash)
   425  	if len(enc) != 0 {
   426  		if db.cleans != nil {
   427  			db.cleans.Set(hash[:], enc)
   428  			memcacheCleanMissMeter.Mark(1)
   429  			memcacheCleanWriteMeter.Mark(int64(len(enc)))
   430  		}
   431  		return enc, nil
   432  	}
   433  	return nil, errors.New("not found")
   434  }
   435  
   436  // Nodes retrieves the hashes of all the nodes cached within the memory database.
   437  // This method is extremely expensive and should only be used to validate internal
   438  // states in test code.
   439  func (db *Database) Nodes() []common.Hash {
   440  	db.lock.RLock()
   441  	defer db.lock.RUnlock()
   442  
   443  	var hashes = make([]common.Hash, 0, len(db.dirties))
   444  	for hash := range db.dirties {
   445  		if hash != (common.Hash{}) { // Special case for "root" references/nodes
   446  			hashes = append(hashes, hash)
   447  		}
   448  	}
   449  	return hashes
   450  }
   451  
   452  // Reference adds a new reference from a parent node to a child node.
   453  // This function is used to add reference between internal trie node
   454  // and external node(e.g. storage trie root), all internal trie nodes
   455  // are referenced together by database itself.
   456  func (db *Database) Reference(child common.Hash, parent common.Hash) {
   457  	db.lock.Lock()
   458  	defer db.lock.Unlock()
   459  
   460  	db.reference(child, parent)
   461  }
   462  
   463  // reference is the private locked version of Reference.
   464  func (db *Database) reference(child common.Hash, parent common.Hash) {
   465  	// If the node does not exist, it's a node pulled from disk, skip
   466  	node, ok := db.dirties[child]
   467  	if !ok {
   468  		return
   469  	}
   470  	// If the reference already exists, only duplicate for roots
   471  	if db.dirties[parent].children == nil {
   472  		db.dirties[parent].children = make(map[common.Hash]uint16)
   473  		db.childrenSize += cachedNodeChildrenSize
   474  	} else if _, ok = db.dirties[parent].children[child]; ok && parent != (common.Hash{}) {
   475  		return
   476  	}
   477  	node.parents++
   478  	db.dirties[parent].children[child]++
   479  	if db.dirties[parent].children[child] == 1 {
   480  		db.childrenSize += common.HashLength + 2 // uint16 counter
   481  	}
   482  }
   483  
   484  // Dereference removes an existing reference from a root node.
   485  func (db *Database) Dereference(root common.Hash) {
   486  	// Sanity check to ensure that the meta-root is not removed
   487  	if root == (common.Hash{}) {
   488  		log.Error("Attempted to dereference the trie cache meta root")
   489  		return
   490  	}
   491  	db.lock.Lock()
   492  	defer db.lock.Unlock()
   493  
   494  	nodes, storage, start := len(db.dirties), db.dirtiesSize, time.Now()
   495  	db.dereference(root, common.Hash{})
   496  
   497  	db.gcnodes += uint64(nodes - len(db.dirties))
   498  	db.gcsize += storage - db.dirtiesSize
   499  	db.gctime += time.Since(start)
   500  
   501  	memcacheGCTimeTimer.Update(time.Since(start))
   502  	memcacheGCSizeMeter.Mark(int64(storage - db.dirtiesSize))
   503  	memcacheGCNodesMeter.Mark(int64(nodes - len(db.dirties)))
   504  
   505  	log.Debug("Dereferenced trie from memory database", "nodes", nodes-len(db.dirties), "size", storage-db.dirtiesSize, "time", time.Since(start),
   506  		"gcnodes", db.gcnodes, "gcsize", db.gcsize, "gctime", db.gctime, "livenodes", len(db.dirties), "livesize", db.dirtiesSize)
   507  }
   508  
   509  // dereference is the private locked version of Dereference.
   510  func (db *Database) dereference(child common.Hash, parent common.Hash) {
   511  	// Dereference the parent-child
   512  	node := db.dirties[parent]
   513  
   514  	if node.children != nil && node.children[child] > 0 {
   515  		node.children[child]--
   516  		if node.children[child] == 0 {
   517  			delete(node.children, child)
   518  			db.childrenSize -= (common.HashLength + 2) // uint16 counter
   519  		}
   520  	}
   521  	// If the child does not exist, it's a previously committed node.
   522  	node, ok := db.dirties[child]
   523  	if !ok {
   524  		return
   525  	}
   526  	// If there are no more references to the child, delete it and cascade
   527  	if node.parents > 0 {
   528  		// This is a special cornercase where a node loaded from disk (i.e. not in the
   529  		// memcache any more) gets reinjected as a new node (short node split into full,
   530  		// then reverted into short), causing a cached node to have no parents. That is
   531  		// no problem in itself, but don't make maxint parents out of it.
   532  		node.parents--
   533  	}
   534  	if node.parents == 0 {
   535  		// Remove the node from the flush-list
   536  		switch child {
   537  		case db.oldest:
   538  			db.oldest = node.flushNext
   539  			db.dirties[node.flushNext].flushPrev = common.Hash{}
   540  		case db.newest:
   541  			db.newest = node.flushPrev
   542  			db.dirties[node.flushPrev].flushNext = common.Hash{}
   543  		default:
   544  			db.dirties[node.flushPrev].flushNext = node.flushNext
   545  			db.dirties[node.flushNext].flushPrev = node.flushPrev
   546  		}
   547  		// Dereference all children and delete the node
   548  		node.forChilds(func(hash common.Hash) {
   549  			db.dereference(hash, child)
   550  		})
   551  		delete(db.dirties, child)
   552  		db.dirtiesSize -= common.StorageSize(common.HashLength + int(node.size))
   553  		if node.children != nil {
   554  			db.childrenSize -= cachedNodeChildrenSize
   555  		}
   556  	}
   557  }
   558  
   559  // Cap iteratively flushes old but still referenced trie nodes until the total
   560  // memory usage goes below the given threshold.
   561  //
   562  // Note, this method is a non-synchronized mutator. It is unsafe to call this
   563  // concurrently with other mutators.
   564  func (db *Database) Cap(limit common.StorageSize) error {
   565  	// Create a database batch to flush persistent data out. It is important that
   566  	// outside code doesn't see an inconsistent state (referenced data removed from
   567  	// memory cache during commit but not yet in persistent storage). This is ensured
   568  	// by only uncaching existing data when the database write finalizes.
   569  	nodes, storage, start := len(db.dirties), db.dirtiesSize, time.Now()
   570  	batch := db.diskdb.NewBatch()
   571  
   572  	// db.dirtiesSize only contains the useful data in the cache, but when reporting
   573  	// the total memory consumption, the maintenance metadata is also needed to be
   574  	// counted.
   575  	size := db.dirtiesSize + common.StorageSize((len(db.dirties)-1)*cachedNodeSize)
   576  	size += db.childrenSize - common.StorageSize(len(db.dirties[common.Hash{}].children)*(common.HashLength+2))
   577  
   578  	// If the preimage cache got large enough, push to disk. If it's still small
   579  	// leave for later to deduplicate writes.
   580  	if db.preimages != nil {
   581  		db.preimages.commit(false)
   582  	}
   583  	// Keep committing nodes from the flush-list until we're below allowance
   584  	oldest := db.oldest
   585  	for size > limit && oldest != (common.Hash{}) {
   586  		// Fetch the oldest referenced node and push into the batch
   587  		node := db.dirties[oldest]
   588  		rawdb.WriteTrieNode(batch, oldest, node.rlp())
   589  
   590  		// If we exceeded the ideal batch size, commit and reset
   591  		if batch.ValueSize() >= ethdb.IdealBatchSize {
   592  			if err := batch.Write(); err != nil {
   593  				log.Error("Failed to write flush list to disk", "err", err)
   594  				return err
   595  			}
   596  			batch.Reset()
   597  		}
   598  		// Iterate to the next flush item, or abort if the size cap was achieved. Size
   599  		// is the total size, including the useful cached data (hash -> blob), the
   600  		// cache item metadata, as well as external children mappings.
   601  		size -= common.StorageSize(common.HashLength + int(node.size) + cachedNodeSize)
   602  		if node.children != nil {
   603  			size -= common.StorageSize(cachedNodeChildrenSize + len(node.children)*(common.HashLength+2))
   604  		}
   605  		oldest = node.flushNext
   606  	}
   607  	// Flush out any remainder data from the last batch
   608  	if err := batch.Write(); err != nil {
   609  		log.Error("Failed to write flush list to disk", "err", err)
   610  		return err
   611  	}
   612  	// Write successful, clear out the flushed data
   613  	db.lock.Lock()
   614  	defer db.lock.Unlock()
   615  
   616  	for db.oldest != oldest {
   617  		node := db.dirties[db.oldest]
   618  		delete(db.dirties, db.oldest)
   619  		db.oldest = node.flushNext
   620  
   621  		db.dirtiesSize -= common.StorageSize(common.HashLength + int(node.size))
   622  		if node.children != nil {
   623  			db.childrenSize -= common.StorageSize(cachedNodeChildrenSize + len(node.children)*(common.HashLength+2))
   624  		}
   625  	}
   626  	if db.oldest != (common.Hash{}) {
   627  		db.dirties[db.oldest].flushPrev = common.Hash{}
   628  	}
   629  	db.flushnodes += uint64(nodes - len(db.dirties))
   630  	db.flushsize += storage - db.dirtiesSize
   631  	db.flushtime += time.Since(start)
   632  
   633  	memcacheFlushTimeTimer.Update(time.Since(start))
   634  	memcacheFlushSizeMeter.Mark(int64(storage - db.dirtiesSize))
   635  	memcacheFlushNodesMeter.Mark(int64(nodes - len(db.dirties)))
   636  
   637  	log.Debug("Persisted nodes from memory database", "nodes", nodes-len(db.dirties), "size", storage-db.dirtiesSize, "time", time.Since(start),
   638  		"flushnodes", db.flushnodes, "flushsize", db.flushsize, "flushtime", db.flushtime, "livenodes", len(db.dirties), "livesize", db.dirtiesSize)
   639  
   640  	return nil
   641  }
   642  
   643  // Commit iterates over all the children of a particular node, writes them out
   644  // to disk, forcefully tearing down all references in both directions. As a side
   645  // effect, all pre-images accumulated up to this point are also written.
   646  //
   647  // Note, this method is a non-synchronized mutator. It is unsafe to call this
   648  // concurrently with other mutators.
   649  func (db *Database) Commit(node common.Hash, report bool, callback func(common.Hash)) error {
   650  	// Create a database batch to flush persistent data out. It is important that
   651  	// outside code doesn't see an inconsistent state (referenced data removed from
   652  	// memory cache during commit but not yet in persistent storage). This is ensured
   653  	// by only uncaching existing data when the database write finalizes.
   654  	start := time.Now()
   655  	batch := db.diskdb.NewBatch()
   656  
   657  	db.lock.Lock()
   658  	for _, v := range db.rawDirties {
   659  		batch.Put(v.K, v.V)
   660  	}
   661  	for k := range db.rawDirties {
   662  		delete(db.rawDirties, k)
   663  	}
   664  	db.lock.Unlock()
   665  	if err := batch.Write(); err != nil {
   666  		return err
   667  	}
   668  	batch.Reset()
   669  
   670  	if (node == common.Hash{}) {
   671  		return nil
   672  	}
   673  
   674  	// Move all of the accumulated preimages into a write batch
   675  	if db.preimages != nil {
   676  		db.preimages.commit(true)
   677  	}
   678  	// Move the trie itself into the batch, flushing if enough data is accumulated
   679  	nodes, storage := len(db.dirties), db.dirtiesSize
   680  
   681  	uncacher := &cleaner{db}
   682  	if err := db.commit(node, batch, uncacher, callback); err != nil {
   683  		log.Error("Failed to commit trie from trie database", "err", err)
   684  		return err
   685  	}
   686  	// Trie mostly committed to disk, flush any batch leftovers
   687  	if err := batch.Write(); err != nil {
   688  		log.Error("Failed to write trie to disk", "err", err)
   689  		return err
   690  	}
   691  	// Uncache any leftovers in the last batch
   692  	db.lock.Lock()
   693  	defer db.lock.Unlock()
   694  
   695  	batch.Replay(uncacher)
   696  	batch.Reset()
   697  
   698  	// Reset the storage counters and bumped metrics
   699  	memcacheCommitTimeTimer.Update(time.Since(start))
   700  	memcacheCommitSizeMeter.Mark(int64(storage - db.dirtiesSize))
   701  	memcacheCommitNodesMeter.Mark(int64(nodes - len(db.dirties)))
   702  
   703  	logger := log.Info
   704  	if !report {
   705  		logger = log.Debug
   706  	}
   707  	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,
   708  		"gcnodes", db.gcnodes, "gcsize", db.gcsize, "gctime", db.gctime, "livenodes", len(db.dirties), "livesize", db.dirtiesSize)
   709  
   710  	// Reset the garbage collection statistics
   711  	db.gcnodes, db.gcsize, db.gctime = 0, 0, 0
   712  	db.flushnodes, db.flushsize, db.flushtime = 0, 0, 0
   713  
   714  	return nil
   715  }
   716  
   717  // commit is the private locked version of Commit.
   718  func (db *Database) commit(hash common.Hash, batch ethdb.Batch, uncacher *cleaner, callback func(common.Hash)) error {
   719  	// If the node does not exist, it's a previously committed node
   720  	node, ok := db.dirties[hash]
   721  	if !ok {
   722  		return nil
   723  	}
   724  	var err error
   725  	node.forChilds(func(child common.Hash) {
   726  		if err == nil {
   727  			err = db.commit(child, batch, uncacher, callback)
   728  		}
   729  	})
   730  	if err != nil {
   731  		return err
   732  	}
   733  	// If we've reached an optimal batch size, commit and start over
   734  	rawdb.WriteTrieNode(batch, hash, node.rlp())
   735  	if callback != nil {
   736  		callback(hash)
   737  	}
   738  	if batch.ValueSize() >= ethdb.IdealBatchSize {
   739  		if err := batch.Write(); err != nil {
   740  			return err
   741  		}
   742  		db.lock.Lock()
   743  		batch.Replay(uncacher)
   744  		batch.Reset()
   745  		db.lock.Unlock()
   746  	}
   747  	return nil
   748  }
   749  
   750  // cleaner is a database batch replayer that takes a batch of write operations
   751  // and cleans up the trie database from anything written to disk.
   752  type cleaner struct {
   753  	db *Database
   754  }
   755  
   756  // Put reacts to database writes and implements dirty data uncaching. This is the
   757  // post-processing step of a commit operation where the already persisted trie is
   758  // removed from the dirty cache and moved into the clean cache. The reason behind
   759  // the two-phase commit is to ensure data availability while moving from memory
   760  // to disk.
   761  func (c *cleaner) Put(key []byte, rlp []byte) error {
   762  	hash := common.BytesToHash(key)
   763  
   764  	// If the node does not exist, we're done on this path
   765  	node, ok := c.db.dirties[hash]
   766  	if !ok {
   767  		return nil
   768  	}
   769  	// Node still exists, remove it from the flush-list
   770  	switch hash {
   771  	case c.db.oldest:
   772  		c.db.oldest = node.flushNext
   773  		c.db.dirties[node.flushNext].flushPrev = common.Hash{}
   774  	case c.db.newest:
   775  		c.db.newest = node.flushPrev
   776  		c.db.dirties[node.flushPrev].flushNext = common.Hash{}
   777  	default:
   778  		c.db.dirties[node.flushPrev].flushNext = node.flushNext
   779  		c.db.dirties[node.flushNext].flushPrev = node.flushPrev
   780  	}
   781  	// Remove the node from the dirty cache
   782  	delete(c.db.dirties, hash)
   783  	c.db.dirtiesSize -= common.StorageSize(common.HashLength + int(node.size))
   784  	if node.children != nil {
   785  		c.db.dirtiesSize -= common.StorageSize(cachedNodeChildrenSize + len(node.children)*(common.HashLength+2))
   786  	}
   787  	// Move the flushed node into the clean cache to prevent insta-reloads
   788  	if c.db.cleans != nil {
   789  		c.db.cleans.Set(hash[:], rlp)
   790  		memcacheCleanWriteMeter.Mark(int64(len(rlp)))
   791  	}
   792  	return nil
   793  }
   794  
   795  func (c *cleaner) Delete(key []byte) error {
   796  	panic("not implemented")
   797  }
   798  
   799  // Size returns the current storage size of the memory cache in front of the
   800  // persistent database layer.
   801  func (db *Database) Size() (common.StorageSize, common.StorageSize) {
   802  	db.lock.RLock()
   803  	defer db.lock.RUnlock()
   804  
   805  	// db.dirtiesSize only contains the useful data in the cache, but when reporting
   806  	// the total memory consumption, the maintenance metadata is also needed to be
   807  	// counted.
   808  	var metadataSize = common.StorageSize((len(db.dirties) - 1) * cachedNodeSize)
   809  	var metarootRefs = common.StorageSize(len(db.dirties[common.Hash{}].children) * (common.HashLength + 2))
   810  	var preimageSize common.StorageSize
   811  	if db.preimages != nil {
   812  		preimageSize = db.preimages.size()
   813  	}
   814  	return db.dirtiesSize + db.childrenSize + metadataSize - metarootRefs, preimageSize
   815  }
   816  
   817  // saveCache saves clean state cache to given directory path
   818  // using specified CPU cores.
   819  func (db *Database) saveCache(dir string, threads int) error {
   820  	if db.cleans == nil {
   821  		return nil
   822  	}
   823  	log.Info("Writing clean trie cache to disk", "path", dir, "threads", threads)
   824  
   825  	start := time.Now()
   826  	err := db.cleans.SaveToFileConcurrent(dir, threads)
   827  	if err != nil {
   828  		log.Error("Failed to persist clean trie cache", "error", err)
   829  		return err
   830  	}
   831  	log.Info("Persisted the clean trie cache", "path", dir, "elapsed", common.PrettyDuration(time.Since(start)))
   832  	return nil
   833  }
   834  
   835  // SaveCache atomically saves fast cache data to the given dir using all
   836  // available CPU cores.
   837  func (db *Database) SaveCache(dir string) error {
   838  	return db.saveCache(dir, runtime.GOMAXPROCS(0))
   839  }
   840  
   841  // SaveCachePeriodically atomically saves fast cache data to the given dir with
   842  // the specified interval. All dump operation will only use a single CPU core.
   843  func (db *Database) SaveCachePeriodically(dir string, interval time.Duration, stopCh <-chan struct{}) {
   844  	ticker := time.NewTicker(interval)
   845  	defer ticker.Stop()
   846  
   847  	for {
   848  		select {
   849  		case <-ticker.C:
   850  			db.saveCache(dir, 1)
   851  		case <-stopCh:
   852  			return
   853  		}
   854  	}
   855  }
   856  
   857  // EmptyRoot indicate what root is for an empty trie, it depends on its underlying implement (zktrie or common trie)
   858  func (db *Database) EmptyRoot() common.Hash {
   859  
   860  	if db.Zktrie {
   861  		return common.Hash{}
   862  	} else {
   863  		return emptyRoot
   864  	}
   865  }