update implementation

core/blockchain.go

@@ -140,8 +140,8 @@ type CacheConfig struct {
 	StateHistory        uint64        // Number of blocks from head whose state histories are reserved.
 	StateScheme         string        // Scheme used to store ethereum states and merkle tree nodes on top
 
-	EnableDiskRootInterval bool          // Enable update disk root when time threshold is reached. Disabled by default
-	DiskRootThreshold      time.Duration // Time threshold after which to flush the layers to disk
+	AllowForceUpdate bool // Enable update disk root when commit threshold is reached. Disabled by default
+	CommitThreshold  int  // Number of commits threshold after which to flush the layers to disk
 
 	SnapshotNoBuild bool // Whether the background generation is allowed
 	SnapshotWait    bool // Wait for snapshot construction on startup. TODO(karalabe): This is a dirty hack for testing, nuke it
@@ -160,9 +160,11 @@ func (c *CacheConfig) triedbConfig(isVerkle bool) *triedb.Config {
 	}
 	if c.StateScheme == rawdb.PathScheme {
 		config.PathDB = &pathdb.Config{
-			StateHistory:   c.StateHistory,
-			CleanCacheSize: c.TrieCleanLimit * 1024 * 1024,
-			DirtyCacheSize: c.TrieDirtyLimit * 1024 * 1024,
+			StateHistory:     c.StateHistory,
+			CleanCacheSize:   c.TrieCleanLimit * 1024 * 1024,
+			DirtyCacheSize:   c.TrieDirtyLimit * 1024 * 1024,
+			AllowForceUpdate: c.AllowForceUpdate,
+			CommitThreshold:  c.CommitThreshold,
 		}
 	}
 	return config
@@ -171,14 +173,14 @@ func (c *CacheConfig) triedbConfig(isVerkle bool) *triedb.Config {
 // defaultCacheConfig are the default caching values if none are specified by the
 // user (also used during testing).
 var defaultCacheConfig = &CacheConfig{
-	TrieCleanLimit:         256,
-	TrieDirtyLimit:         256,
-	TrieTimeLimit:          5 * time.Minute,
-	SnapshotLimit:          256,
-	SnapshotWait:           true,
-	StateScheme:            rawdb.HashScheme,
-	EnableDiskRootInterval: false,
-	DiskRootThreshold:      60 * time.Minute,
+	TrieCleanLimit:   256,
+	TrieDirtyLimit:   256,
+	TrieTimeLimit:    5 * time.Minute,
+	SnapshotLimit:    256,
+	SnapshotWait:     true,
+	StateScheme:      rawdb.HashScheme,
+	AllowForceUpdate: false,
+	CommitThreshold:  128,
 }
 
 // DefaultCacheConfigWithScheme returns a deep copied default cache config with
@@ -446,12 +448,12 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, genesis *Genesis
 			recover = true
 		}
 		snapconfig := snapshot.Config{
-			CacheSize:              bc.cacheConfig.SnapshotLimit,
-			Recovery:               recover,
-			NoBuild:                bc.cacheConfig.SnapshotNoBuild,
-			AsyncBuild:             !bc.cacheConfig.SnapshotWait,
-			EnableDiskRootInterval: bc.cacheConfig.EnableDiskRootInterval,
-			DiskRootThreshold:      bc.cacheConfig.DiskRootThreshold,
+			CacheSize:        bc.cacheConfig.SnapshotLimit,
+			Recovery:         recover,
+			NoBuild:          bc.cacheConfig.SnapshotNoBuild,
+			AsyncBuild:       !bc.cacheConfig.SnapshotWait,
+			AllowForceUpdate: bc.cacheConfig.AllowForceUpdate,
+			CommitThreshold:  bc.cacheConfig.CommitThreshold,
 		}
 		bc.snaps, _ = snapshot.New(snapconfig, bc.db, bc.triedb, head.Root)
 	}

core/blockchain_repair_test.go

@@ -1820,7 +1820,7 @@ func testRepairWithScheme(t *testing.T, tt *rewindTest, snapshots bool, scheme s
 			t.Fatalf("Failed to flush trie state: %v", err)
 		}
 		if snapshots {
-			if err := chain.snaps.Cap(canonblocks[tt.commitBlock-1].Root(), 0); err != nil {
+			if err := chain.snaps.Cap(canonblocks[tt.commitBlock-1].Root(), 0, false); err != nil {
 				t.Fatalf("Failed to flatten snapshots: %v", err)
 			}
 		}
@@ -1950,7 +1950,7 @@ func testIssue23496(t *testing.T, scheme string) {
 	if _, err := chain.InsertChain(blocks[1:2]); err != nil {
 		t.Fatalf("Failed to import canonical chain start: %v", err)
 	}
-	if err := chain.snaps.Cap(blocks[1].Root(), 0); err != nil {
+	if err := chain.snaps.Cap(blocks[1].Root(), 0, false); err != nil {
 		t.Fatalf("Failed to flatten snapshots: %v", err)
 	}
 

core/blockchain_sethead_test.go

@@ -2023,7 +2023,7 @@ func testSetHeadWithScheme(t *testing.T, tt *rewindTest, snapshots bool, scheme
 	if tt.commitBlock > 0 {
 		chain.triedb.Commit(canonblocks[tt.commitBlock-1].Root(), false)
 		if snapshots {
-			if err := chain.snaps.Cap(canonblocks[tt.commitBlock-1].Root(), 0); err != nil {
+			if err := chain.snaps.Cap(canonblocks[tt.commitBlock-1].Root(), 0, false); err != nil {
 				t.Fatalf("Failed to flatten snapshots: %v", err)
 			}
 		}

core/blockchain_snapshot_test.go

@@ -108,7 +108,7 @@ func (basic *snapshotTestBasic) prepare(t *testing.T) (*BlockChain, []*types.Blo
 			// Flushing the entire snap tree into the disk, the
 			// relevant (a) snapshot root and (b) snapshot generator
 			// will be persisted atomically.
-			chain.snaps.Cap(blocks[point-1].Root(), 0)
+			chain.snaps.Cap(blocks[point-1].Root(), 0, false)
 			diskRoot, blockRoot := chain.snaps.DiskRoot(), blocks[point-1].Root()
 			if !bytes.Equal(diskRoot.Bytes(), blockRoot.Bytes()) {
 				t.Fatalf("Failed to flush disk layer change, want %x, got %x", blockRoot, diskRoot)

core/state/pruner/pruner.go

@@ -192,7 +192,7 @@ func prune(snaptree *snapshot.Tree, root common.Hash, maindb ethdb.Database, sta
 	// Pruning is done, now drop the "useless" layers from the snapshot.
 	// Firstly, flushing the target layer into the disk. After that all
 	// diff layers below the target will all be merged into the disk.
-	if err := snaptree.Cap(root, 0); err != nil {
+	if err := snaptree.Cap(root, 0, false); err != nil {
 		return err
 	}
 	// Secondly, flushing the snapshot journal into the disk. All diff

core/state/snapshot/difflayer.go

@@ -77,8 +77,10 @@ var (
 	bloomAccountHasherOffset  = 0
 	bloomStorageHasherOffset  = 0
 
-	// Setting a minimum to prevent very low input from user
-	minTimeThreshold = 1 * time.Minute
+	// Count for number of commits before force disk update
+	// after the first 128 layers, the 129 layers would be committed
+	// to disk.
+	defaultCommitThreshold = 128
 )
 
 func init() {

core/state/snapshot/disklayer_test.go

@@ -133,7 +133,7 @@ func TestDiskMerge(t *testing.T) {
 	}); err != nil {
 		t.Fatalf("failed to update snapshot tree: %v", err)
 	}
-	if err := snaps.Cap(diffRoot, 0); err != nil {
+	if err := snaps.Cap(diffRoot, 0, false); err != nil {
 		t.Fatalf("failed to flatten snapshot tree: %v", err)
 	}
 	// Retrieve all the data through the disk layer and validate it
@@ -356,7 +356,7 @@ func TestDiskPartialMerge(t *testing.T) {
 		}); err != nil {
 			t.Fatalf("test %d: failed to update snapshot tree: %v", i, err)
 		}
-		if err := snaps.Cap(diffRoot, 0); err != nil {
+		if err := snaps.Cap(diffRoot, 0, false); err != nil {
 			t.Fatalf("test %d: failed to flatten snapshot tree: %v", i, err)
 		}
 		// Retrieve all the data through the disk layer and validate it
@@ -467,7 +467,7 @@ func TestDiskGeneratorPersistence(t *testing.T) {
 	}, nil); err != nil {
 		t.Fatalf("failed to update snapshot tree: %v", err)
 	}
-	if err := snaps.Cap(diffRoot, 0); err != nil {
+	if err := snaps.Cap(diffRoot, 0, false); err != nil {
 		t.Fatalf("failed to flatten snapshot tree: %v", err)
 	}
 	blob := rawdb.ReadSnapshotGenerator(db)
@@ -489,7 +489,7 @@ func TestDiskGeneratorPersistence(t *testing.T) {
 	}
 	diskLayer := snaps.layers[snaps.diskRoot()].(*diskLayer)
 	diskLayer.genMarker = nil // Construction finished
-	if err := snaps.Cap(diffTwoRoot, 0); err != nil {
+	if err := snaps.Cap(diffTwoRoot, 0, false); err != nil {
 		t.Fatalf("failed to flatten snapshot tree: %v", err)
 	}
 	blob = rawdb.ReadSnapshotGenerator(db)

core/state/snapshot/iterator_test.go

@@ -248,7 +248,7 @@ func TestAccountIteratorTraversal(t *testing.T) {
 		aggregatorMemoryLimit = limit
 	}()
 	aggregatorMemoryLimit = 0 // Force pushing the bottom-most layer into disk
-	snaps.Cap(common.HexToHash("0x04"), 2)
+	snaps.Cap(common.HexToHash("0x04"), 2, false)
 	verifyIterator(t, 7, head.(*diffLayer).newBinaryAccountIterator(), verifyAccount)
 
 	it, _ = snaps.AccountIterator(common.HexToHash("0x04"), common.Hash{})
@@ -296,7 +296,7 @@ func TestStorageIteratorTraversal(t *testing.T) {
 		aggregatorMemoryLimit = limit
 	}()
 	aggregatorMemoryLimit = 0 // Force pushing the bottom-most layer into disk
-	snaps.Cap(common.HexToHash("0x04"), 2)
+	snaps.Cap(common.HexToHash("0x04"), 2, false)
 	verifyIterator(t, 6, head.(*diffLayer).newBinaryStorageIterator(common.HexToHash("0xaa")), verifyStorage)
 
 	it, _ = snaps.StorageIterator(common.HexToHash("0x04"), common.HexToHash("0xaa"), common.Hash{})
@@ -384,7 +384,7 @@ func TestAccountIteratorTraversalValues(t *testing.T) {
 		aggregatorMemoryLimit = limit
 	}()
 	aggregatorMemoryLimit = 0 // Force pushing the bottom-most layer into disk
-	snaps.Cap(common.HexToHash("0x09"), 2)
+	snaps.Cap(common.HexToHash("0x09"), 2, false)
 
 	it, _ = snaps.AccountIterator(common.HexToHash("0x09"), common.Hash{})
 	for it.Next() {
@@ -483,7 +483,7 @@ func TestStorageIteratorTraversalValues(t *testing.T) {
 		aggregatorMemoryLimit = limit
 	}()
 	aggregatorMemoryLimit = 0 // Force pushing the bottom-most layer into disk
-	snaps.Cap(common.HexToHash("0x09"), 2)
+	snaps.Cap(common.HexToHash("0x09"), 2, false)
 
 	it, _ = snaps.StorageIterator(common.HexToHash("0x09"), common.HexToHash("0xaa"), common.Hash{})
 	for it.Next() {
@@ -541,7 +541,7 @@ func TestAccountIteratorLargeTraversal(t *testing.T) {
 		aggregatorMemoryLimit = limit
 	}()
 	aggregatorMemoryLimit = 0 // Force pushing the bottom-most layer into disk
-	snaps.Cap(common.HexToHash("0x80"), 2)
+	snaps.Cap(common.HexToHash("0x80"), 2, false)
 
 	verifyIterator(t, 200, head.(*diffLayer).newBinaryAccountIterator(), verifyAccount)
 
@@ -580,7 +580,7 @@ func TestAccountIteratorFlattening(t *testing.T) {
 	it, _ := snaps.AccountIterator(common.HexToHash("0x04"), common.Hash{})
 	defer it.Release()
 
-	if err := snaps.Cap(common.HexToHash("0x04"), 1); err != nil {
+	if err := snaps.Cap(common.HexToHash("0x04"), 1, false); err != nil {
 		t.Fatalf("failed to flatten snapshot stack: %v", err)
 	}
 	//verifyIterator(t, 7, it)

core/state/snapshot/snapshot.go

@@ -22,7 +22,6 @@ import (
 	"errors"
 	"fmt"
 	"sync"
-	"time"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/rawdb"
@@ -151,12 +150,23 @@ type snapshot interface {
 
 // Config includes the configurations for snapshots.
 type Config struct {
-	CacheSize              int           // Megabytes permitted to use for read caches
-	Recovery               bool          // Indicator that the snapshots is in the recovery mode
-	NoBuild                bool          // Indicator that the snapshots generation is disallowed
-	AsyncBuild             bool          // The snapshot generation is allowed to be constructed asynchronously
-	EnableDiskRootInterval bool          // The disk root is allowed to update after a time threshold
-	DiskRootThreshold      time.Duration // The threshold to update disk root
+	CacheSize        int  // Megabytes permitted to use for read caches
+	Recovery         bool // Indicator that the snapshots is in the recovery mode
+	NoBuild          bool // Indicator that the snapshots generation is disallowed
+	AsyncBuild       bool // The snapshot generation is allowed to be constructed asynchronously
+	AllowForceUpdate bool // Enable forcing snap root generation on a commit count
+	CommitThreshold  int  // Number of commit after which to attempt snap root update
+}
+
+// sanitize checks the provided user configurations and changes anything that's
+// unreasonable or unworkable.
+func (c *Config) sanitize() Config {
+	conf := *c
+
+	if conf.CommitThreshold == 0 {
+		conf.CommitThreshold = defaultCommitThreshold
+	}
+	return conf
 }
 
 // Tree is an Ethereum state snapshot tree. It consists of one persistent base
@@ -169,12 +179,12 @@ type Config struct {
 // storage data to avoid expensive multi-level trie lookups; and to allow sorted,
 // cheap iteration of the account/storage tries for sync aid.
 type Tree struct {
-	config   Config                   // Snapshots configurations
-	diskdb   ethdb.KeyValueStore      // Persistent database to store the snapshot
-	triedb   *triedb.Database         // In-memory cache to access the trie through
-	layers   map[common.Hash]snapshot // Collection of all known layers
-	lock     sync.RWMutex
-	baseTime time.Time // Reference to calculate the time threshold
+	config        Config                   // Snapshots configurations
+	diskdb        ethdb.KeyValueStore      // Persistent database to store the snapshot
+	triedb        *triedb.Database         // In-memory cache to access the trie through
+	layers        map[common.Hash]snapshot // Collection of all known layers
+	lock          sync.RWMutex
+	commitCounter int // Counter for number of commits
 
 	// Test hooks
 	onFlatten func() // Hook invoked when the bottom most diff layers are flattened
@@ -199,17 +209,13 @@ type Tree struct {
 func New(config Config, diskdb ethdb.KeyValueStore, triedb *triedb.Database, root common.Hash) (*Tree, error) {
 	// Create a new, empty snapshot tree
 	snap := &Tree{
-		config:   config,
-		diskdb:   diskdb,
-		triedb:   triedb,
-		layers:   make(map[common.Hash]snapshot),
-		baseTime: time.Now(),
+		config: config,
+		diskdb: diskdb,
+		triedb: triedb,
+		layers: make(map[common.Hash]snapshot),
 	}
 
-	// If user provided threshold smaller than minimum, set to minimum
-	if config.DiskRootThreshold < minTimeThreshold {
-		config.DiskRootThreshold = minTimeThreshold
-	}
+	config = config.sanitize()
 
 	// Attempt to load a previously persisted snapshot and rebuild one if failed
 	head, disabled, err := loadSnapshot(diskdb, triedb, root, config.CacheSize, config.Recovery, config.NoBuild)
@@ -393,7 +399,7 @@ func (t *Tree) Update(blockRoot common.Hash, parentRoot common.Hash, destructs m
 // which may or may not overflow and cascade to disk. Since this last layer's
 // survival is only known *after* capping, we need to omit it from the count if
 // we want to ensure that *at least* the requested number of diff layers remain.
-func (t *Tree) Cap(root common.Hash, layers int) error {
+func (t *Tree) Cap(root common.Hash, layers int, force bool) error {
 	// Retrieve the head snapshot to cap from
 	snap := t.Snapshot(root)
 	if snap == nil {
@@ -427,7 +433,7 @@ func (t *Tree) Cap(root common.Hash, layers int) error {
 		t.layers = map[common.Hash]snapshot{base.root: base}
 		return nil
 	}
-	persisted := t.cap(diff, layers)
+	persisted := t.cap(diff, layers, force)
 
 	// Remove any layer that is stale or links into a stale layer
 	children := make(map[common.Hash][]common.Hash)
@@ -477,7 +483,7 @@ func (t *Tree) Cap(root common.Hash, layers int) error {
 // which may or may not overflow and cascade to disk. Since this last layer's
 // survival is only known *after* capping, we need to omit it from the count if
 // we want to ensure that *at least* the requested number of diff layers remain.
-func (t *Tree) cap(diff *diffLayer, layers int) *diskLayer {
+func (t *Tree) cap(diff *diffLayer, layers int, force bool) *diskLayer {
 	// Dive until we run out of layers or reach the persistent database
 	for i := 0; i < layers-1; i++ {
 		// If we still have diff layers below, continue down
@@ -511,7 +517,7 @@ func (t *Tree) cap(diff *diffLayer, layers int) *diskLayer {
 			t.onFlatten()
 		}
 		diff.parent = flattened
-		if (flattened.memory < aggregatorMemoryLimit) && !t.isPastThreshold() {
+		if (flattened.memory < aggregatorMemoryLimit) && !force {
 			// Accumulator layer is smaller than the limit, so we can abort, unless
 			// there's a snapshot being generated currently. In that case, the trie
 			// will move from underneath the generator so we **must** merge all the
@@ -530,9 +536,6 @@ func (t *Tree) cap(diff *diffLayer, layers int) *diskLayer {
 	base := diffToDisk(bottom)
 	bottom.lock.RUnlock()
 
-	// Reset the time reference for next update
-	t.baseTime = time.Now()
-
 	t.layers[base.root] = base
 	diff.parent = base
 	return base
@@ -900,8 +903,19 @@ func (t *Tree) Size() (diffs common.StorageSize, buf common.StorageSize) {
 	return size, 0
 }
 
-// Check if time threshold is enabled and if the time elapsed is more than the threshold.
-// if false, we can abort else we proceed to update the disk root
-func (t *Tree) isPastThreshold() bool {
-	return (t.config.EnableDiskRootInterval && (time.Since(t.baseTime) > t.config.DiskRootThreshold))
+// Checks the config to compare if count of commits is above threshold
+func (t *Tree) CompareThreshold() bool {
+	if !t.config.AllowForceUpdate {
+		return false
+	}
+
+	log.Debug("Snapshot Commit counters", "counter", t.commitCounter, "threshold", t.config.CommitThreshold)
+	if t.commitCounter > t.config.CommitThreshold {
+		t.commitCounter = 0
+		return true
+	}
+
+	t.commitCounter++
+
+	return false
 }