core: fix some comment

core/blockchain.go

@@ -165,7 +165,7 @@ 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
 	PathSyncFlush       bool          // Whether sync flush the trienodebuffer of pathdb to disk.
-	JournalFile         string        // whether enable TrieJournal store in wal
+	JournalFile         string        // whether enable TrieJournal store in journal file
 
 	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

eth/backend.go

@@ -252,8 +252,10 @@ func New(stack *node.Node, config *ethconfig.Config) (*Ethereum, error) {
 			rawdb.WriteDatabaseVersion(chainDb, core.BlockChainVersion)
 		}
 	}
-	var journalFile string
-	var path string
+	var (
+		journalFile string
+		path        string
+	)
 	if config.JournalFileEnabled {
 		if stack.IsSeparatedDB() {
 			path = ChainData + "/state"

eth/ethconfig/config.go

@@ -119,7 +119,7 @@ type Config struct {
 	// consistent with persistent state.
 	StateScheme        string `toml:",omitempty"` // State scheme used to store ethereum state and merkle trie nodes on top
 	PathSyncFlush      bool   `toml:",omitempty"` // State scheme used to store ethereum state and merkle trie nodes on top
-	JournalFileEnabled bool   // Enable the in-memory trie node layers to store to wal file when shutdown
+	JournalFileEnabled bool   // Enable the TrieJournal to store to journal file when shutdown
 
 	// RequiredBlocks is a set of block number -> hash mappings which must be in the
 	// canonical chain of all remote peers. Setting the option makes geth verify the

triedb/pathdb/database.go

@@ -102,7 +102,7 @@ type Config struct {
 	DirtyCacheSize int    // Maximum memory allowance (in bytes) for caching dirty nodes
 	ReadOnly       bool   // Flag whether the database is opened in read only mode.
 	NoTries        bool
-	JournalFile    string // whether enable TrieJournal store in wal
+	JournalFile    string // whether enable TrieJournal store in journal file
 }
 
 // sanitize checks the provided user configurations and changes anything that's