diff --git a/source/dnode/vnode/src/tsdb/tsdbFS2.c b/source/dnode/vnode/src/tsdb/tsdbFS2.c
index 8cf3b9400d..3b8aa075be 100644
--- a/source/dnode/vnode/src/tsdb/tsdbFS2.c
+++ b/source/dnode/vnode/src/tsdb/tsdbFS2.c
@@ -260,7 +260,7 @@ static int32_t apply_commit(STFileSystem *fs) {
         TARRAY2_REMOVE(fsetArray1, i1, tsdbTFileSetRemove);
       } else if (fset1->fid > fset2->fid) {
         // create new file set with fid of fset2->fid
-        code = tsdbTFileSetInitEx(fs->tsdb, fset2, &fset1);
+        code = tsdbTFileSetInitDup(fs->tsdb, fset2, &fset1);
         if (code) return code;
         code = TARRAY2_SORT_INSERT(fsetArray1, fset1, tsdbTFileSetCmprFn);
         if (code) return code;
@@ -278,7 +278,7 @@ static int32_t apply_commit(STFileSystem *fs) {
       TARRAY2_REMOVE(fsetArray1, i1, tsdbTFileSetRemove);
     } else {
       // create new file set with fid of fset2->fid
-      code = tsdbTFileSetInitEx(fs->tsdb, fset2, &fset1);
+      code = tsdbTFileSetInitDup(fs->tsdb, fset2, &fset1);
       if (code) return code;
       code = TARRAY2_SORT_INSERT(fsetArray1, fset1, tsdbTFileSetCmprFn);
       if (code) return code;
@@ -383,7 +383,7 @@ static int32_t tsdbFSDupState(STFileSystem *fs) {
   const STFileSet *fset1;
   TARRAY2_FOREACH(src, fset1) {
     STFileSet *fset2;
-    code = tsdbTFileSetInitEx(fs->tsdb, fset1, &fset2);
+    code = tsdbTFileSetInitDup(fs->tsdb, fset1, &fset2);
     if (code) return code;
     code = TARRAY2_APPEND(dst, fset2);
     if (code) return code;
@@ -656,7 +656,7 @@ int32_t tsdbFSCreateCopySnapshot(STFileSystem *fs, TFileSetArray **fsetArr) {
 
   taosThreadRwlockRdlock(&fs->tsdb->rwLock);
   TARRAY2_FOREACH(fs->fSetArr, fset) {
-    code = tsdbTFileSetInitEx(fs->tsdb, fset, &fset1);
+    code = tsdbTFileSetInitDup(fs->tsdb, fset, &fset1);
     if (code) break;
 
     code = TARRAY2_APPEND(fsetArr[0], fset1);
@@ -689,7 +689,8 @@ int32_t tsdbFSCreateRefSnapshot(STFileSystem *fs, TFileSetArray **fsetArr) {
 
   taosThreadRwlockRdlock(&fs->tsdb->rwLock);
   TARRAY2_FOREACH(fs->fSetArr, fset) {
-    // TODO: create ref fset of fset1
+    code = tsdbTFileSetInitRef(fs->tsdb, fset, &fset1);
+    if (code) break;
 
     code = TARRAY2_APPEND(fsetArr[0], fset1);
     if (code) break;
@@ -697,7 +698,7 @@ int32_t tsdbFSCreateRefSnapshot(STFileSystem *fs, TFileSetArray **fsetArr) {
   taosThreadRwlockUnlock(&fs->tsdb->rwLock);
 
   if (code) {
-    TARRAY2_DESTROY(fsetArr[0], NULL /* TODO */);
+    TARRAY2_DESTROY(fsetArr[0], tsdbTFileSetClear);
     fsetArr[0] = NULL;
   }
   return code;
@@ -705,7 +706,7 @@ int32_t tsdbFSCreateRefSnapshot(STFileSystem *fs, TFileSetArray **fsetArr) {
 
 int32_t tsdbFSDestroyRefSnapshot(TFileSetArray **fsetArr) {
   if (fsetArr[0]) {
-    TARRAY2_DESTROY(fsetArr[0], NULL /* TODO */);
+    TARRAY2_DESTROY(fsetArr[0], tsdbTFileSetClear);
     fsetArr[0] = NULL;
   }
   return 0;
diff --git a/source/dnode/vnode/src/tsdb/tsdbFSet2.c b/source/dnode/vnode/src/tsdb/tsdbFSet2.c
index ed908d0b15..7cbbfcfef7 100644
--- a/source/dnode/vnode/src/tsdb/tsdbFSet2.c
+++ b/source/dnode/vnode/src/tsdb/tsdbFSet2.c
@@ -48,6 +48,19 @@ static int32_t tsdbSttLvlInitEx(STsdb *pTsdb, const SSttLvl *lvl1, SSttLvl **lvl
   return 0;
 }
 
+static int32_t tsdbSttLvlInitRef(STsdb *pTsdb, const SSttLvl *lvl1, SSttLvl **lvl) {
+  int32_t code = tsdbSttLvlInit(lvl1->level, lvl);
+  if (code) return code;
+
+  STFileObj *fobj1;
+  TARRAY2_FOREACH(lvl1->fobjArr, fobj1) {
+    tsdbTFileObjRef(fobj1);
+    code = TARRAY2_APPEND(lvl[0]->fobjArr, fobj1);
+    if (code) return code;
+  }
+  return 0;
+}
+
 static void tsdbSttLvlRemoveFObj(void *data) { tsdbTFileObjRemove(*(STFileObj **)data); }
 static void tsdbSttLvlRemove(SSttLvl **lvl) {
   TARRAY2_DESTROY(lvl[0]->fobjArr, tsdbSttLvlRemoveFObj);
@@ -405,7 +418,7 @@ int32_t tsdbTFileSetInit(int32_t fid, STFileSet **fset) {
   return 0;
 }
 
-int32_t tsdbTFileSetInitEx(STsdb *pTsdb, const STFileSet *fset1, STFileSet **fset) {
+int32_t tsdbTFileSetInitDup(STsdb *pTsdb, const STFileSet *fset1, STFileSet **fset) {
   int32_t code = tsdbTFileSetInit(fset1->fid, fset);
   if (code) return code;
 
@@ -435,6 +448,33 @@ int32_t tsdbTFileSetInitEx(STsdb *pTsdb, const STFileSet *fset1, STFileSet **fse
   return 0;
 }
 
+int32_t tsdbTFileSetInitRef(STsdb *pTsdb, const STFileSet *fset1, STFileSet **fset) {
+  int32_t code = tsdbTFileSetInit(fset1->fid, fset);
+  if (code) return code;
+
+  for (int32_t ftype = TSDB_FTYPE_MIN; ftype < TSDB_FTYPE_MAX; ++ftype) {
+    if (fset1->farr[ftype] == NULL) continue;
+
+    tsdbTFileObjRef(fset1->farr[ftype]);
+    fset[0]->farr[ftype] = fset1->farr[ftype];
+  }
+
+  const SSttLvl *lvl1;
+  TARRAY2_FOREACH(fset1->lvlArr, lvl1) {
+    SSttLvl *lvl;
+    code = tsdbSttLvlInitRef(pTsdb, lvl1, &lvl);
+    if (code) {
+      tsdbTFileSetClear(fset);
+      return code;
+    }
+
+    code = TARRAY2_APPEND(fset[0]->lvlArr, lvl);
+    if (code) return code;
+  }
+
+  return 0;
+}
+
 int32_t tsdbTFileSetClear(STFileSet **fset) {
   if (!fset[0]) return 0;
 
diff --git a/source/dnode/vnode/src/tsdb/tsdbFSet2.h b/source/dnode/vnode/src/tsdb/tsdbFSet2.h
index 2663ecd3b9..075acd6394 100644
--- a/source/dnode/vnode/src/tsdb/tsdbFSet2.h
+++ b/source/dnode/vnode/src/tsdb/tsdbFSet2.h
@@ -41,7 +41,8 @@ typedef enum {
 
 // init/clear
 int32_t tsdbTFileSetInit(int32_t fid, STFileSet **fset);
-int32_t tsdbTFileSetInitEx(STsdb *pTsdb, const STFileSet *fset1, STFileSet **fset);
+int32_t tsdbTFileSetInitDup(STsdb *pTsdb, const STFileSet *fset1, STFileSet **fset);
+int32_t tsdbTFileSetInitRef(STsdb *pTsdb, const STFileSet *fset1, STFileSet **fset);
 int32_t tsdbTFileSetClear(STFileSet **fset);
 int32_t tsdbTFileSetRemove(STFileSet **fset);
 // to/from json