diff --git a/weed/storage/needle_map/memdb.go b/weed/storage/needle_map/memdb.go
index a80a7870c..b25b5e89a 100644
--- a/weed/storage/needle_map/memdb.go
+++ b/weed/storage/needle_map/memdb.go
@@ -88,7 +88,7 @@ func (cm *MemDb) SaveToIdx(idxName string) (ret error) {
 	defer idxFile.Close()
 
 	return cm.AscendingVisit(func(value NeedleValue) error {
-		if value.Offset.IsZero() || value.Size == TombstoneFileSize {
+		if value.Offset.IsZero() || value.Size.IsDeleted() {
 			return nil
 		}
 		_, err := idxFile.Write(value.ToBytes())
@@ -105,7 +105,7 @@ func (cm *MemDb) LoadFromIdx(idxName string) (ret error) {
 	defer idxFile.Close()
 
 	return idx.WalkIndexFile(idxFile, func(key NeedleId, offset Offset, size Size) error {
-		if offset.IsZero() || size == TombstoneFileSize {
+		if offset.IsZero() || size.IsDeleted() {
 			return cm.Delete(key)
 		}
 		return cm.Set(key, offset, size)
diff --git a/weed/storage/needle_map_sorted_file.go b/weed/storage/needle_map_sorted_file.go
index c89916f67..1ca113ca9 100644
--- a/weed/storage/needle_map_sorted_file.go
+++ b/weed/storage/needle_map_sorted_file.go
@@ -80,7 +80,7 @@ func (m *SortedFileNeedleMap) Delete(key NeedleId, offset Offset) error {
 		return err
 	}
 
-	if size == TombstoneFileSize {
+	if size.IsDeleted() {
 		return nil
 	}
 
diff --git a/weed/storage/types/needle_types.go b/weed/storage/types/needle_types.go
index c8234aa49..138643f7f 100644
--- a/weed/storage/types/needle_types.go
+++ b/weed/storage/types/needle_types.go
@@ -15,6 +15,10 @@ type Offset struct {
 
 type Size uint32
 
+func (s Size) IsDeleted() bool {
+	return s == TombstoneFileSize
+}
+
 type OffsetLower struct {
 	b3 byte
 	b2 byte
diff --git a/weed/storage/volume_checking.go b/weed/storage/volume_checking.go
index 36c6628aa..7a5a423b4 100644
--- a/weed/storage/volume_checking.go
+++ b/weed/storage/volume_checking.go
@@ -27,7 +27,7 @@ func CheckVolumeDataIntegrity(v *Volume, indexFile *os.File) (lastAppendAtNs uin
 	if offset.IsZero() {
 		return 0, nil
 	}
-	if size == TombstoneFileSize {
+	if size.IsDeleted() {
 		size = 0
 	}
 	if lastAppendAtNs, e = verifyNeedleIntegrity(v.DataBackend, v.Version(), offset.ToAcutalOffset(), key, size); e != nil {
diff --git a/weed/storage/volume_read_write.go b/weed/storage/volume_read_write.go
index fa1a80cbd..d7b477a2d 100644
--- a/weed/storage/volume_read_write.go
+++ b/weed/storage/volume_read_write.go
@@ -260,7 +260,7 @@ func (v *Volume) readNeedle(n *needle.Needle) (int, error) {
 	if !ok || nv.Offset.IsZero() {
 		return -1, ErrorNotFound
 	}
-	if nv.Size == TombstoneFileSize {
+	if nv.Size.IsDeleted() {
 		return -1, errors.New("already deleted")
 	}
 	if nv.Size == 0 {
diff --git a/weed/storage/volume_vacuum.go b/weed/storage/volume_vacuum.go
index 505af50bb..9d366a27d 100644
--- a/weed/storage/volume_vacuum.go
+++ b/weed/storage/volume_vacuum.go
@@ -413,7 +413,7 @@ func copyDataBasedOnIndexFile(srcDatName, srcIdxName, dstDatName, datIdxName str
 
 		offset, size := value.Offset, value.Size
 
-		if offset.IsZero() || size == TombstoneFileSize {
+		if offset.IsZero() || size.IsDeleted() {
 			return nil
 		}