cmd, core, eth, light, trie: add trie read caching layer

2 files changed, 24 insertions, 11 deletions

diff --git a/core/blockchain.go b/core/blockchain.go
index 26ac75b8c..22f130ce6 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -68,9 +68,10 @@ const (
 // CacheConfig contains the configuration values for the trie caching/pruning
 // that's resident in a blockchain.
 type CacheConfig struct {
-	Disabled      bool          // Whether to disable trie write caching (archive node)
-	TrieNodeLimit int           // Memory limit (MB) at which to flush the current in-memory trie to disk
-	TrieTimeLimit time.Duration // Time limit after which to flush the current in-memory trie to disk
+	Disabled       bool          // Whether to disable trie write caching (archive node)
+	TrieCleanLimit int           // Memory allowance (MB) to use for caching trie nodes in memory
+	TrieDirtyLimit int           // Memory limit (MB) at which to start flushing dirty trie nodes to disk
+	TrieTimeLimit  time.Duration // Time limit after which to flush the current in-memory trie to disk
 }
 
 // BlockChain represents the canonical chain given a database with a genesis
@@ -140,8 +141,9 @@ type BlockChain struct {
 func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *params.ChainConfig, engine consensus.Engine, vmConfig vm.Config, shouldPreserve func(block *types.Block) bool) (*BlockChain, error) {
 	if cacheConfig == nil {
 		cacheConfig = &CacheConfig{
-			TrieNodeLimit: 256,
-			TrieTimeLimit: 5 * time.Minute,
+			TrieCleanLimit: 256,
+			TrieDirtyLimit: 256,
+			TrieTimeLimit:  5 * time.Minute,
 		}
 	}
 	bodyCache, _ := lru.New(bodyCacheLimit)
@@ -156,7 +158,7 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *par
 		cacheConfig:    cacheConfig,
 		db:             db,
 		triegc:         prque.New(nil),
-		stateCache:     state.NewDatabase(db),
+		stateCache:     state.NewDatabaseWithCache(db, cacheConfig.TrieCleanLimit),
 		quit:           make(chan struct{}),
 		shouldPreserve: shouldPreserve,
 		bodyCache:      bodyCache,
@@ -393,6 +395,11 @@ func (bc *BlockChain) StateAt(root common.Hash) (*state.StateDB, error) {
 	return state.New(root, bc.stateCache)
 }
 
+// StateCache returns the caching database underpinning the blockchain instance.
+func (bc *BlockChain) StateCache() state.Database {
+	return bc.stateCache
+}
+
 // Reset purges the entire blockchain, restoring it to its genesis state.
 func (bc *BlockChain) Reset() error {
 	return bc.ResetWithGenesisBlock(bc.genesisBlock)
@@ -938,7 +945,7 @@ func (bc *BlockChain) WriteBlockWithState(block *types.Block, receipts []*types.
 			// If we exceeded our memory allowance, flush matured singleton nodes to disk
 			var (
 				nodes, imgs = triedb.Size()
-				limit       = common.StorageSize(bc.cacheConfig.TrieNodeLimit) * 1024 * 1024
+				limit       = common.StorageSize(bc.cacheConfig.TrieDirtyLimit) * 1024 * 1024
 			)
 			if nodes > limit || imgs > 4*1024*1024 {
 				triedb.Cap(limit - ethdb.IdealBatchSize)
diff --git a/core/state/database.go b/core/state/database.go
index c1b630991..f6ea144b9 100644
--- a/core/state/database.go
+++ b/core/state/database.go
@@ -72,13 +72,19 @@ type Trie interface {
 }
 
 // NewDatabase creates a backing store for state. The returned database is safe for
-// concurrent use and retains cached trie nodes in memory. The pool is an optional
-// intermediate trie-node memory pool between the low level storage layer and the
-// high level trie abstraction.
+// concurrent use and retains a few recent expanded trie nodes in memory. To keep
+// more historical state in memory, use the NewDatabaseWithCache constructor.
 func NewDatabase(db ethdb.Database) Database {
+	return NewDatabaseWithCache(db, 0)
+}
+
+// NewDatabase creates a backing store for state. The returned database is safe for
+// concurrent use and retains both a few recent expanded trie nodes in memory, as
+// well as a lot of collapsed RLP trie nodes in a large memory cache.
+func NewDatabaseWithCache(db ethdb.Database, cache int) Database {
 	csc, _ := lru.New(codeSizeCacheSize)
 	return &cachingDB{
-		db:            trie.NewDatabase(db),
+		db:            trie.NewDatabaseWithCache(db, cache),
 		codeSizeCache: csc,
 	}
 }