diff --git a/source/dnode/vnode/src/tsdb/dev/inc/tsdbFile.h b/source/dnode/vnode/src/tsdb/dev/inc/tsdbFile.h
index abc24b8018c371d9aaef2ad299f2e83de1194eaa..cfe3c0ea8768de4623c2889f3a5fddd1b74cb829 100644
--- a/source/dnode/vnode/src/tsdb/dev/inc/tsdbFile.h
+++ b/source/dnode/vnode/src/tsdb/dev/inc/tsdbFile.h
@@ -55,7 +55,7 @@ struct STFile {
   int64_t      size;
   union {
     struct {
-      int32_t lvl;
+      int32_t level;
       int32_t nseg;
     } stt;
   };
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbFSet.c b/source/dnode/vnode/src/tsdb/dev/tsdbFSet.c
index 1edead748d82c9f9c729a441919446090c3022f7..bd8be47ce832e78ea1514c60cd58ed1ca1bd1e23 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbFSet.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbFSet.c
@@ -16,7 +16,7 @@
 #include "inc/tsdbFSet.h"
 
 static int32_t stt_lvl_to_json(const SSttLvl *lvl, cJSON *json) {
-  if (cJSON_AddNumberToObject(json, "lvl", lvl->level) == NULL) {
+  if (cJSON_AddNumberToObject(json, "level", lvl->level) == NULL) {
     return TSDB_CODE_OUT_OF_MEMORY;
   }
 
@@ -65,7 +65,7 @@ static int32_t add_file_to_stt_lvl(SSttLvl *lvl, STFileObj *fobj) {
 static int32_t json_to_stt_lvl(const cJSON *json, SSttLvl *lvl) {
   const cJSON *item1, *item2;
 
-  item1 = cJSON_GetObjectItem(json, "lvl");
+  item1 = cJSON_GetObjectItem(json, "level");
   if (cJSON_IsNumber(item1)) {
     lvl->level = item1->valuedouble;
   } else {
@@ -102,7 +102,7 @@ static int32_t add_stt_lvl(STFileSet *fset, SSttLvl *lvl) {
 static int32_t add_file_to_fset(STFileSet *fset, STFileObj *fobj) {
   if (fobj->f.type == TSDB_FTYPE_STT) {
     SSttLvl *lvl;
-    SSttLvl  tlvl = {.level = fobj->f.stt.lvl};
+    SSttLvl  tlvl = {.level = fobj->f.stt.level};
 
     SRBTreeNode *node = tRBTreeGet(&fset->lvlTree, &tlvl.rbtn);
     if (node) {
@@ -111,7 +111,7 @@ static int32_t add_file_to_fset(STFileSet *fset, STFileObj *fobj) {
       lvl = taosMemoryMalloc(sizeof(*lvl));
       if (!lvl) return TSDB_CODE_OUT_OF_MEMORY;
 
-      stt_lvl_init(lvl, fobj->f.stt.lvl);
+      stt_lvl_init(lvl, fobj->f.stt.level);
       add_stt_lvl(fset, lvl);
     }
     add_file_to_stt_lvl(lvl, fobj);
@@ -150,6 +150,7 @@ static int32_t fset_clear(STFileSet *fset) {
 
 int32_t tsdbFileSetToJson(const STFileSet *fset, cJSON *json) {
   int32_t code = 0;
+  cJSON  *item1, *item2;
 
   // fid
   if (cJSON_AddNumberToObject(json, "fid", fset->fid) == NULL) {
@@ -164,13 +165,15 @@ int32_t tsdbFileSetToJson(const STFileSet *fset, cJSON *json) {
   }
 
   // each level
-  cJSON *ajson = cJSON_AddArrayToObject(json, "stt");
-  if (ajson == NULL) return TSDB_CODE_OUT_OF_MEMORY;
-
+  item1 = cJSON_AddArrayToObject(json, "stt levels");
+  if (item1 == NULL) return TSDB_CODE_OUT_OF_MEMORY;
   SRBTreeIter iter = tRBTreeIterCreate(&fset->lvlTree, 1);
   for (SRBTreeNode *node = tRBTreeIterNext(&iter); node; node = tRBTreeIterNext(&iter)) {
-    SSttLvl *lvl = TCONTAINER_OF(node, SSttLvl, rbtn);
-    code = stt_lvl_to_json(lvl, ajson);
+    item2 = cJSON_CreateObject();
+    if (!item2) return TSDB_CODE_OUT_OF_MEMORY;
+    cJSON_AddItemToArray(item1, item2);
+
+    code = stt_lvl_to_json(TCONTAINER_OF(node, SSttLvl, rbtn), item2);
     if (code) return code;
   }
 
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbFile.c b/source/dnode/vnode/src/tsdb/dev/tsdbFile.c
index 9ad13adbd923614aab787b4548e1402b3acbc9fe..33c18ddf0a8210fa27f8d2c08944a1a5d68c6059 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbFile.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbFile.c
@@ -125,7 +125,7 @@ static int32_t stt_to_json(const STFile *file, cJSON *json) {
   if (code) return code;
 
   /* lvl */
-  if (cJSON_AddNumberToObject(json, "lvl", file->stt.lvl) == NULL) {
+  if (cJSON_AddNumberToObject(json, "level", file->stt.level) == NULL) {
     return TSDB_CODE_OUT_OF_MEMORY;
   }
 
@@ -148,9 +148,9 @@ static int32_t stt_from_json(const cJSON *json, STFile *file) {
   const cJSON *item;
 
   /* lvl */
-  item = cJSON_GetObjectItem(json, "lvl");
+  item = cJSON_GetObjectItem(json, "level");
   if (cJSON_IsNumber(item)) {
-    file->stt.lvl = item->valuedouble;
+    file->stt.level = item->valuedouble;
   } else {
     return TSDB_CODE_FILE_CORRUPTED;
   }