diff --git a/storage/extent_store.go b/storage/extent_store.go
index fc8d0a8c3..f8818bf6a 100644
--- a/storage/extent_store.go
+++ b/storage/extent_store.go
@@ -1033,7 +1033,7 @@ func (s *ExtentStore) GetStoreUsedSize() (used int64) {
 				continue
 			}
 			if log.EnableDebug() {
-				log.LogDebugf("[GetStoreUsedSize] store(%v) tiny extent(%v) size(%v)", s.dataPath, einfo.FileID, strutil.FormatSize(uint64(size)))
+				log.LogDebugf("[GetStoreUsedSize] store(%v) tiny extent(%v) size(%v) raw(%v)", s.dataPath, einfo.FileID, strutil.FormatSize(uint64(size)), size)
 			}
 			used += size
 			tinyTotal += uint64(size)
@@ -1046,10 +1046,14 @@ func (s *ExtentStore) GetStoreUsedSize() (used int64) {
 				}
 				actualSize, err := s.getFileDiskUsed(path.Join(s.dataPath, strconv.FormatInt(int64(einfo.FileID), 10)))
 				if err != nil {
-					log.LogErrorf("[GetStoreUsedSize] store(%v) failed to get normal extent(%v) disk used", s.dataPath, einfo.FileID)
+					if os.IsNotExist(err) {
+						log.LogInfof("[GetStoreUsedSize] store(%v) extent(%v) already be deleted, skip", s.dataPath, einfo.FileID)
+						continue
+					}
+					log.LogErrorf("[GetStoreUsedSize] store(%v) failed to get normal extent(%v) disk used, err(%v)", s.dataPath, einfo.FileID, err)
 					continue
 				}
-				log.LogDebugf("[GetStoreUsedSize] store(%v) normal extent(%v) size(%v), actual size(%v)", s.dataPath, einfo.FileID, strutil.FormatSize(uint64(size)), strutil.FormatSize(uint64(actualSize)))
+				log.LogDebugf("[GetStoreUsedSize] store(%v) normal extent(%v) size(%v) raw(%v), actual size(%v) raw(%v)", s.dataPath, einfo.FileID, strutil.FormatSize(uint64(size)), size, strutil.FormatSize(uint64(actualSize)), actualSize)
 				if actualSize < size {
 					log.LogWarnf("[GetStoreUsedSize] store(%v) normal extent(%v) actual size(%v), size(%v) einfo size(%v) snapshot off(%v)", s.dataPath, einfo.FileID, strutil.FormatSize(uint64(actualSize)), strutil.FormatSize(uint64(size)), strutil.FormatSize(einfo.Size), strutil.FormatSize(einfo.SnapshotDataOff))
 				}
@@ -1059,7 +1063,7 @@ func (s *ExtentStore) GetStoreUsedSize() (used int64) {
 		}
 	}
 	if log.EnableInfo() {
-		log.LogInfof("[GetStoreUsedSize] store(%v) total size(%v) tiny total(%v) normal total(%v)", s.dataPath, strutil.FormatSize(uint64(used)), strutil.FormatSize(tinyTotal), strutil.FormatSize(normalTotal))
+		log.LogInfof("[GetStoreUsedSize] store(%v) total size(%v) raw(%v) tiny total(%v) raw(%v) normal total(%v) raw(%v)", s.dataPath, strutil.FormatSize(uint64(used)), used, strutil.FormatSize(tinyTotal), tinyTotal, strutil.FormatSize(normalTotal), normalTotal)
 	}
 	return
 }
diff --git a/util/strutil/fmt.go b/util/strutil/fmt.go
index 0a7258ace..b9e035219 100644
--- a/util/strutil/fmt.go
+++ b/util/strutil/fmt.go
@@ -49,7 +49,7 @@ func ParseSize(sizeStr string) (size uint64, err error) {
 }
 
 type SuffixPair struct {
-	Size   uint64
+	Size   float64
 	Suffix string
 }
 
@@ -84,22 +84,7 @@ func FormatSize(size uint64) (sizeStr string) {
 	if size == 0 {
 		return "0"
 	}
-	var pair SuffixPair
-	for _, suffixPair := range suffixTable {
-		if size >= suffixPair.Size {
-			pair = suffixPair
-			continue
-		}
-		break
-	}
-	if pair.Size == 0 {
-		sizeStr = fmt.Sprintf("invalid %v", size)
-	} else {
-		size /= pair.Size
-		sizeStr = fmt.Sprintf("%v%v", size, pair.Suffix)
-	}
-
-	return
+	return FormatSizeFloat(float64(size))
 }
 
 func ParsePercent(valStr string) (val float64, err error) {
@@ -120,3 +105,27 @@ func FormatPercent(val float64) (valStr string) {
 	valStr = fmt.Sprintf("%v%%", val*100)
 	return
 }
+
+func formatFloatAndTrimSuffix(v float64) (str string) {
+	str = fmt.Sprintf("%.3f", v)
+	str = strings.TrimSuffix(str, ".000")
+	return
+}
+
+func FormatSizeFloat(val float64) (sizeStr string) {
+	if val <= 1 {
+		sizeStr = formatFloatAndTrimSuffix(val)
+		return
+	}
+	var pair SuffixPair
+	for _, suffixPair := range suffixTable {
+		if val >= suffixPair.Size {
+			pair = suffixPair
+			continue
+		}
+		break
+	}
+	val /= float64(pair.Size)
+	sizeStr = fmt.Sprintf("%v%v", formatFloatAndTrimSuffix(val), pair.Suffix)
+	return
+}