diff --git a/src/client/src/tscProfile.c b/src/client/src/tscProfile.c
index f48e7b7691536cb8f9a5b8561e95b8a5a0f0fefc..6ff97e9d00ad9cbf8cd6fdc92713b111a497c321 100644
--- a/src/client/src/tscProfile.c
+++ b/src/client/src/tscProfile.c
@@ -285,9 +285,9 @@ void tscKillConnection(STscObj *pObj) {
 
   SSqlObj *pSql = pObj->sqlList;
   while (pSql) {
-    //taosStopRpcConn(pSql->thandle);
     pSql = pSql->next;
   }
+  
 
   SSqlStream *pStream = pObj->streamList;
   while (pStream) {
diff --git a/src/client/src/tscServer.c b/src/client/src/tscServer.c
index 9282fa74fbab3e32f8332b69d3800d84c37e5dd6..4f179adf72320c971dc74ccf28b12f4d022a17fc 100644
--- a/src/client/src/tscServer.c
+++ b/src/client/src/tscServer.c
@@ -226,13 +226,17 @@ int tscSendMsgToServer(SSqlObj *pSql) {
       .handle  = &pSql->pRpcCtx,
       .code    = 0
   };
-
   // NOTE: the rpc context should be acquired before sending data to server.
   // Otherwise, the pSql object may have been released already during the response function, which is
   // processMsgFromServer function. In the meanwhile, the assignment of the rpc context to sql object will absolutely
   // cause crash.
-  rpcSendRequest(pObj->pDnodeConn, &pSql->epSet, &rpcMsg);
-  return TSDB_CODE_SUCCESS;
+  if (pObj != NULL && pObj->signature == pObj) {
+    rpcSendRequest(pObj->pDnodeConn, &pSql->epSet, &rpcMsg);
+    return TSDB_CODE_SUCCESS;
+  } else {
+    //pObj->signature has been reset by other thread, ignore concurrency problem
+    return TSDB_CODE_TSC_CONN_KILLED; 
+  }
 }
 
 void tscProcessMsgFromServer(SRpcMsg *rpcMsg, SRpcEpSet *pEpSet) {
diff --git a/src/inc/taoserror.h b/src/inc/taoserror.h
index 57c2b322faee5f56a5b8e1f1fe38a597a63a0b9e..e2ba7b03c143a0772e6cb959580a6c1ad3bd69d2 100644
--- a/src/inc/taoserror.h
+++ b/src/inc/taoserror.h
@@ -96,6 +96,7 @@ TAOS_DEFINE_ERROR(TSDB_CODE_TSC_APP_ERROR,                0, 0x0211, "Applicatio
 TAOS_DEFINE_ERROR(TSDB_CODE_TSC_ACTION_IN_PROGRESS,       0, 0x0212, "Action in progress")
 TAOS_DEFINE_ERROR(TSDB_CODE_TSC_DISCONNECTED,             0, 0x0213, "Disconnected from service")
 TAOS_DEFINE_ERROR(TSDB_CODE_TSC_NO_WRITE_AUTH,            0, 0x0214, "No write permission")
+TAOS_DEFINE_ERROR(TSDB_CODE_TSC_CONN_KILLED,            0, 0x0215, "Connection killed")
 
 // mnode
 TAOS_DEFINE_ERROR(TSDB_CODE_MND_MSG_NOT_PROCESSED,        0, 0x0300, "Message not processed")
diff --git a/src/mnode/src/mnodeProfile.c b/src/mnode/src/mnodeProfile.c
index 85457d7a26b84adfd383d447c84604c15a436cee..06f992c26a4b2fd6eec19abb9743e4add2536000 100644
--- a/src/mnode/src/mnodeProfile.c
+++ b/src/mnode/src/mnodeProfile.c
@@ -100,7 +100,7 @@ SConnObj *mnodeCreateConn(char *user, uint32_t ip, uint16_t port) {
   };
   tstrncpy(connObj.user, user, sizeof(connObj.user));
   
-  SConnObj *pConn = taosCachePut(tsMnodeConnCache, &connId, sizeof(int32_t), &connObj, sizeof(connObj), CONN_KEEP_TIME);
+  SConnObj *pConn = taosCachePut(tsMnodeConnCache, &connId, sizeof(int32_t), &connObj, sizeof(connObj), CONN_KEEP_TIME * 1000);
 
   mDebug("connId:%d, is created, user:%s ip:%s:%u", connId, user, taosIpStr(ip), port);
   return pConn;