diff --git a/src/client/src/tscPrepare.c b/src/client/src/tscPrepare.c
index 665efa4c6dbca0437540ee1dd9875267bc2d8b72..8e4c417fbfe759bc383191b9d7a9b49f41978435 100644
--- a/src/client/src/tscPrepare.c
+++ b/src/client/src/tscPrepare.c
@@ -1261,8 +1261,6 @@ static void insertBatchClean(STscStmt* pStmt) {
   taosHashClear(pCmd->insertParam.pTableBlockHashList);
   tscFreeSqlResult(pSql);
   tscFreeSubobj(pSql);
-  tfree(pSql->pSubs);
-  pSql->subState.numOfSub = 0;
 }
 
 static int insertBatchStmtExecute(STscStmt* pStmt) {
diff --git a/src/client/src/tscServer.c b/src/client/src/tscServer.c
index 92a6f6e149306a7449c823311aaa92061974d39d..779847d7c89deb35f6747e2c89c17cc061ce6445 100644
--- a/src/client/src/tscServer.c
+++ b/src/client/src/tscServer.c
@@ -330,7 +330,7 @@ void checkBrokenQueries(STscObj *pTscObj) {
   SSqlObj *pSql = pTscObj->sqlList;
   while (pSql) {
     // avoid sqlobj may not be correctly removed from sql list
-    if (pSql->sqlstr == NULL) {
+    if (pSql->sqlstr == NULL || pSql->signature != pSql) {
       pSql = pSql->next;
       continue;
     }
@@ -3392,7 +3392,6 @@ int tscRenewTableMeta(SSqlObj *pSql) {
   pthread_mutex_lock(&rootSql->mtxSubs);
   tscFreeSubobj(rootSql);
   pthread_mutex_unlock(&rootSql->mtxSubs);
-  tfree(rootSql->pSubs);
   tscResetSqlCmd(&rootSql->cmd, true, rootSql->self);
 
   code = getMultiTableMetaFromMnode(rootSql, pNameList, vgroupList, NULL, tscTableMetaCallBack, true);
diff --git a/src/client/src/tscStream.c b/src/client/src/tscStream.c
index 0ed4c0a270ca675dfc445f387ad48de5171df7d9..eab9527f16e439e48016faff33a280c206818e15 100644
--- a/src/client/src/tscStream.c
+++ b/src/client/src/tscStream.c
@@ -232,8 +232,6 @@ static void tscProcessStreamQueryCallback(void *param, TAOS_RES *tres, int numOf
 
     tscFreeSqlResult(pStream->pSql);
     tscFreeSubobj(pStream->pSql);
-    tfree(pStream->pSql->pSubs);
-    pStream->pSql->subState.numOfSub = 0;
 
     pTableMetaInfo->vgroupList = tscVgroupInfoClear(pTableMetaInfo->vgroupList);
     tscSetRetryTimer(pStream, pStream->pSql, retryDelay);
@@ -610,8 +608,6 @@ static void tscProcessStreamRetrieveResult(void *param, TAOS_RES *res, int numOf
 
     tscFreeSqlResult(pSql);
     tscFreeSubobj(pSql);    
-    tfree(pSql->pSubs);
-    pSql->subState.numOfSub = 0;
     pTableMetaInfo->vgroupList = tscVgroupInfoClear(pTableMetaInfo->vgroupList);
     tscSetNextLaunchTimer(pStream, pSql);
   }
diff --git a/src/client/src/tscSubquery.c b/src/client/src/tscSubquery.c
index 1805c22a9d77181fd5d5e2b3f31a25186741ac74..a8c2eea195992c4a6e66cbfd49bf9e36f2cf4c8c 100644
--- a/src/client/src/tscSubquery.c
+++ b/src/client/src/tscSubquery.c
@@ -695,6 +695,12 @@ static int32_t tscLaunchRealSubqueries(SSqlObj* pSql) {
 }
 
 void freeJoinSubqueryObj(SSqlObj* pSql) {
+  if (pSql->subState.numOfSub == 0) {
+    return;
+  }  
+
+  pthread_mutex_lock(&pSql->subState.mutex);
+
   for (int32_t i = 0; i < pSql->subState.numOfSub; ++i) {
     SSqlObj* pSub = pSql->pSubs[i];
     if (pSub == NULL) {
@@ -707,13 +713,13 @@ void freeJoinSubqueryObj(SSqlObj* pSql) {
     taos_free_result(pSub);
     pSql->pSubs[i] = NULL;
   }
-
-  if (pSql->subState.states) {
-    pthread_mutex_destroy(&pSql->subState.mutex);
-  }
   
   tfree(pSql->subState.states);
   pSql->subState.numOfSub = 0;
+
+  pthread_mutex_unlock(&pSql->subState.mutex);
+
+  pthread_mutex_destroy(&pSql->subState.mutex);  
 }
 
 static int32_t quitAllSubquery(SSqlObj* pSqlSub, SSqlObj* pSqlObj, SJoinSupporter* pSupporter) {
@@ -901,7 +907,6 @@ bool tscReparseSql(SSqlObj *sql, int32_t code){
   }
 
   tscFreeSubobj(sql);      
-  tfree(sql->pSubs);
 
   sql->res.code = TSDB_CODE_SUCCESS;
   sql->retry++;
@@ -2180,7 +2185,6 @@ void tscHandleMasterJoinQuery(SSqlObj* pSql) {
   assert((pQueryInfo->type & TSDB_QUERY_TYPE_SUBQUERY) == 0);
 
   int32_t code = TSDB_CODE_SUCCESS;
-  pSql->subState.numOfSub = pQueryInfo->numOfTables;
 
   if (pSql->subState.states == NULL) {
     pSql->subState.states = calloc(pSql->subState.numOfSub, sizeof(*pSql->subState.states));
@@ -2192,6 +2196,8 @@ void tscHandleMasterJoinQuery(SSqlObj* pSql) {
     pthread_mutex_init(&pSql->subState.mutex, NULL);
   }
 
+  pSql->subState.numOfSub = pQueryInfo->numOfTables;
+
   memset(pSql->subState.states, 0, sizeof(*pSql->subState.states) * pSql->subState.numOfSub);
   tscDebug("0x%"PRIx64" reset all sub states to 0, start subquery, total:%d", pSql->self, pQueryInfo->numOfTables);
 
@@ -2251,7 +2257,12 @@ void tscHandleMasterJoinQuery(SSqlObj* pSql) {
 }
 
 void doCleanupSubqueries(SSqlObj *pSql, int32_t numOfSubs) {
-  assert(numOfSubs <= pSql->subState.numOfSub && numOfSubs >= 0);
+  pthread_mutex_lock(&pSql->subState.mutex);
+  if (numOfSubs > pSql->subState.numOfSub || numOfSubs <= 0 || pSql->subState.numOfSub <= 0) {
+    pthread_mutex_unlock(&pSql->subState.mutex);
+    return;
+  }
+
   
   for(int32_t i = 0; i < numOfSubs; ++i) {
     SSqlObj* pSub = pSql->pSubs[i];
@@ -2261,6 +2272,7 @@ void doCleanupSubqueries(SSqlObj *pSql, int32_t numOfSubs) {
     
     taos_free_result(pSub);
   }
+  pthread_mutex_unlock(&pSql->subState.mutex);
 }
 
 void tscLockByThread(int64_t *lockedBy) {
@@ -2365,8 +2377,10 @@ void tscFirstRoundRetrieveCallback(void* param, TAOS_RES* tres, int numOfRows) {
   if (code != TSDB_CODE_SUCCESS) {
     tscFreeFirstRoundSup(&param);
     taos_free_result(pSql);
+    pthread_mutex_lock(&pParent->subState.mutex);
     pParent->subState.numOfSub = 0;
     tfree(pParent->pSubs);    
+    pthread_mutex_unlock(&pParent->subState.mutex);
     pParent->res.code = code;
     tscAsyncResultOnError(pParent);
     return;
@@ -2469,9 +2483,11 @@ void tscFirstRoundRetrieveCallback(void* param, TAOS_RES* tres, int numOfRows) {
   tscFreeFirstRoundSup(&param);
 
   taos_free_result(pSql);
+  pthread_mutex_lock(&pParent->subState.mutex);
   pParent->subState.numOfSub = 0;
   tfree(pParent->pSubs);    
-
+  pthread_mutex_unlock(&pParent->subState.mutex);
+  
   if (resRows == 0) {
     pParent->cmd.command = TSDB_SQL_RETRIEVE_EMPTY_RESULT;
     (*pParent->fp)(pParent->param, pParent, 0);
@@ -2493,8 +2509,10 @@ void tscFirstRoundCallback(void* param, TAOS_RES* tres, int code) {
 
     tscFreeFirstRoundSup(&param);
     taos_free_result(pSql);
+    pthread_mutex_lock(&parent->subState.mutex);
     parent->subState.numOfSub = 0;
     tfree(parent->pSubs);
+    pthread_mutex_unlock(&parent->subState.mutex);
     parent->res.code = c;
     tscAsyncResultOnError(parent);
     return;
@@ -3014,7 +3032,6 @@ void tscHandleSubqueryError(SRetrieveSupport *trsupport, SSqlObj *pSql, int numO
       }
 
       tscFreeSubobj(userSql);      
-      tfree(userSql->pSubs);
 
       userSql->res.code = TSDB_CODE_SUCCESS;
       userSql->retry++;
@@ -3382,7 +3399,9 @@ static bool needRetryInsert(SSqlObj* pParentObj, int32_t numOfSub) {
 }
 
 static void doFreeInsertSupporter(SSqlObj* pSqlObj) {
-  assert(pSqlObj != NULL && pSqlObj->subState.numOfSub > 0);
+  if (pSqlObj == NULL || pSqlObj->subState.numOfSub <= 0) {
+    return;
+  }
 
   for(int32_t i = 0; i < pSqlObj->subState.numOfSub; ++i) {
     SSqlObj* pSql = pSqlObj->pSubs[i];
diff --git a/src/client/src/tscUtil.c b/src/client/src/tscUtil.c
index 6c03aeefd789825ddabe1cf1a27bf1f5f28995ea..e1717269de6d2152acc127e6d704080e3e57b62d 100644
--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -1682,6 +1682,8 @@ void tscFreeSubobj(SSqlObj* pSql) {
     return;
   }
 
+  pthread_mutex_lock(&pSql->subState.mutex);
+
   tscDebug("0x%"PRIx64" start to free sub SqlObj, numOfSub:%d", pSql->self, pSql->subState.numOfSub);
 
   for(int32_t i = 0; i < pSql->subState.numOfSub; ++i) {
@@ -1695,12 +1697,14 @@ void tscFreeSubobj(SSqlObj* pSql) {
     pSql->pSubs[i] = NULL;
   }
 
-  if (pSql->subState.states) {
-    pthread_mutex_destroy(&pSql->subState.mutex);
-  }
-
   tfree(pSql->subState.states);
   pSql->subState.numOfSub = 0;
+
+  tfree(pSql->pSubs);
+
+  pthread_mutex_unlock(&pSql->subState.mutex);
+  
+  pthread_mutex_destroy(&pSql->subState.mutex);
 }
 
 /**
@@ -1768,9 +1772,6 @@ void tscFreeSqlObj(SSqlObj* pSql) {
   pSql->fp = NULL;
   tfree(pSql->sqlstr);
   tfree(pSql->pBuf);
-
-  tfree(pSql->pSubs);
-  pSql->subState.numOfSub = 0;
   pSql->self = 0;
 
   tscFreeSqlResult(pSql);
@@ -4161,10 +4162,7 @@ static void tscSubqueryCompleteCallback(void* param, TAOS_RES* tres, int code) {
     }
 
     tscFreeSubobj(pParentSql);
-    tfree(pParentSql->pSubs);
-
     tscFreeSubobj(rootObj);
-    tfree(rootObj->pSubs);
 
     rootObj->res.code = TSDB_CODE_SUCCESS;
     rootObj->retry++;
@@ -4207,19 +4205,9 @@ static void tscSubqueryCompleteCallback(void* param, TAOS_RES* tres, int code) {
 int32_t doInitSubState(SSqlObj* pSql, int32_t numOfSubqueries) {
   //bug fix. Above doInitSubState level, the loop invocation with the same SSqlObj will be fail.
   //assert(pSql->subState.numOfSub == 0 && pSql->pSubs == NULL && pSql->subState.states == NULL);  
-  if(pSql->pSubs) {
-    free(pSql->pSubs);
-    pSql->pSubs = NULL;
-  }
-  
-  if(pSql->subState.states) {
-    free(pSql->subState.states);
-    pSql->subState.states = NULL;
-  }
-  
-  pSql->subState.numOfSub = numOfSubqueries;
+  tscFreeSubobj(pSql);
   
-  pSql->pSubs = calloc(pSql->subState.numOfSub, POINTER_BYTES);
+  pSql->pSubs = calloc(numOfSubqueries, POINTER_BYTES);
   pSql->subState.states = calloc(pSql->subState.numOfSub, sizeof(int8_t));
 
   int32_t code = pthread_mutex_init(&pSql->subState.mutex, NULL);
@@ -4227,6 +4215,8 @@ int32_t doInitSubState(SSqlObj* pSql, int32_t numOfSubqueries) {
     return TSDB_CODE_TSC_OUT_OF_MEMORY;
   }
 
+  pSql->subState.numOfSub = numOfSubqueries;
+
   return TSDB_CODE_SUCCESS;
 }
 
@@ -4332,6 +4322,7 @@ void executeQuery(SSqlObj* pSql, SQueryInfo* pQueryInfo) {
   return;
 
   _error:
+
   for(int32_t i = 0; i < numOfInit; ++i) {
     SSqlObj* p = pSql->pSubs[i];
     tscFreeSqlObj(p);
@@ -4616,16 +4607,7 @@ void tscTryQueryNextClause(SSqlObj* pSql, __async_cb_func_t fp) {
   pRes->final = finalBk;
   pRes->numOfTotal = num;
 
-  pthread_mutex_lock(&pSql->subState.mutex);
-  for(int32_t i = 0; i < pSql->subState.numOfSub; ++i) {
-    taos_free_result(pSql->pSubs[i]);
-  }
-
-  tfree(pSql->pSubs);
-  tfree(pSql->subState.states);
-  pSql->subState.numOfSub = 0;
-  pthread_mutex_unlock(&pSql->subState.mutex);
-  pthread_mutex_destroy(&pSql->subState.mutex);
+  tscFreeSubobj(pSql);
 
   pSql->fp = fp;
 
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 6ba582138c2aecbad0c0dde95177b67a4a0d72fb..7ff2ff790fe5e1d98f147fb4e4f0e2ea7e13b43b 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -9946,7 +9946,7 @@ SQInfo* createQInfoImpl(SQueryTableMsg* pQueryMsg, SGroupbyExpr* pGroupbyExpr, S
 
     pTableqinfo->pGroupList = taosArrayInit(numOfGroups, POINTER_BYTES);
     pTableqinfo->numOfTables = pTableGroupInfo->numOfTables;
-    pTableqinfo->map = taosHashInit(pTableGroupInfo->numOfTables, taosGetDefaultHashFunction(TSDB_DATA_TYPE_INT), true, HASH_NO_LOCK);
+    pTableqinfo->map = taosHashInit(pTableGroupInfo->numOfTables, taosGetDefaultHashFunction(TSDB_DATA_TYPE_INT), true, HASH_ENTRY_LOCK);
   }
 
   pQInfo->pBuf = calloc(pTableGroupInfo->numOfTables, sizeof(STableQueryInfo));
@@ -10146,10 +10146,13 @@ static void doDestroyTableQueryInfo(STableGroupInfo* pTableqinfoGroupInfo) {
   }
 
   taosArrayDestroy(&pTableqinfoGroupInfo->pGroupList);
-  taosHashCleanup(pTableqinfoGroupInfo->map);
+
+  SHashObj *pmap = pTableqinfoGroupInfo->map;
+  if (pmap == atomic_val_compare_exchange_ptr(&pTableqinfoGroupInfo->map, pmap, NULL)) {
+    taosHashCleanup(pmap);
+  }
 
   pTableqinfoGroupInfo->pGroupList = NULL;
-  pTableqinfoGroupInfo->map = NULL;
   pTableqinfoGroupInfo->numOfTables = 0;
 }
 
diff --git a/src/util/src/hash.c b/src/util/src/hash.c
index d4d42976155cb1e11b4abdf6c1d6fa6855921971..3cbcc7ed6e7243dc1dcaec17b3c35892c011461e 100644
--- a/src/util/src/hash.c
+++ b/src/util/src/hash.c
@@ -611,7 +611,6 @@ void taosHashClear(SHashObj *pHashObj) {
   for (int32_t i = 0; i < pHashObj->capacity; ++i) {
     SHashEntry *pEntry = pHashObj->hashList[i];
     if (pEntry->num == 0) {
-      assert(pEntry->next == NULL);
       continue;
     }