moss lowerLevelUpdate didn't handle batches of size 1

index/store/moss/lower.go

@@ -55,9 +55,11 @@ func initLowerLevelStore(
 	}
 
 	llStore := &llStore{
-		refs:    0,
-		kvStore: kvStore,
-		logf:    logf,
+		refs:     0,
+		config:   config,
+		llConfig: lowerLevelStoreConfig,
+		kvStore:  kvStore,
+		logf:     logf,
 	}
 
 	llUpdate := func(ssHigher moss.Snapshot) (ssLower moss.Snapshot, err error) {
@@ -80,6 +82,9 @@ func initLowerLevelStore(
 type llStore struct {
 	kvStore store.KVStore
 
+	config   map[string]interface{}
+	llConfig map[string]interface{}
+
 	logf func(format string, a ...interface{})
 
 	m    sync.Mutex // Protects fields that follow.
@@ -219,6 +224,8 @@ func (s *llStore) update(ssHigher moss.Snapshot, maxBatchSize uint64) (
 					" unexpected operation, ex: %v", ex)
 			}
 
+			i++
+
 			err = iter.Next()
 			if err == moss.ErrIteratorDone {
 				break
@@ -240,19 +247,19 @@ func (s *llStore) update(ssHigher moss.Snapshot, maxBatchSize uint64) (
 
 				batch = kvWriter.NewBatch()
 			}
-
-			i++
 		}
 
 		if i > 0 {
-			s.logf("llStore.update, total: %d, ExecuteBatch: ...", i)
+			s.logf("llStore.update, ExecuteBatch,"+
+				" path: %s, total: %d, start", s.llConfig["path"], i)
 
 			err = kvWriter.ExecuteBatch(batch)
 			if err != nil {
 				return nil, err
 			}
 
-			s.logf("llStore.update, total: %d, ExecuteBatch: done", i)
+			s.logf("llStore.update, ExecuteBatch,"+
+				" path: %s: total: %d, done", s.llConfig["path"], i)
 		}
 	}
 

index/store/moss/store.go

@@ -82,7 +82,7 @@ func New(mo store.MergeOperator, config map[string]interface{}) (
 
 	// --------------------------------------------------
 
-	if options.Log == nil {
+	if options.Log == nil || options.Debug <= 0 {
 		options.Log = func(format string, a ...interface{}) {}
 	}