diff --git a/include/common/tmsg.h b/include/common/tmsg.h
index 136a576c7c..b7e0c7cba4 100644
--- a/include/common/tmsg.h
+++ b/include/common/tmsg.h
@@ -1125,7 +1125,6 @@ int32_t tDeserializeSSchedulerHbReq(void* buf, int32_t bufLen, SSchedulerHbReq*
 void    tFreeSSchedulerHbReq(SSchedulerHbReq* pReq);
 
 typedef struct {
-  uint64_t       seqId;
   SQueryNodeEpId epId;
   SArray*        taskStatus;  // SArray<STaskStatus>
 } SSchedulerHbRsp;
diff --git a/include/common/tmsgcb.h b/include/common/tmsgcb.h
index 64e399770b..1b3311b400 100644
--- a/include/common/tmsgcb.h
+++ b/include/common/tmsgcb.h
@@ -28,6 +28,7 @@ typedef struct SMgmtWrapper SMgmtWrapper;
 typedef enum {
   QUERY_QUEUE,
   FETCH_QUEUE,
+  READ_QUEUE,
   WRITE_QUEUE,
   APPLY_QUEUE,
   SYNC_QUEUE,
diff --git a/include/common/tmsgdef.h b/include/common/tmsgdef.h
index 8d49479d31..051ee34644 100644
--- a/include/common/tmsgdef.h
+++ b/include/common/tmsgdef.h
@@ -212,6 +212,10 @@ enum {
   TD_DEF_MSG_TYPE(TDMT_SND_TASK_PIPE_EXEC, "snode-task-pipe-exec", SStreamTaskExecReq, SStreamTaskExecRsp)
   TD_DEF_MSG_TYPE(TDMT_SND_TASK_MERGE_EXEC, "snode-task-merge-exec", SStreamTaskExecReq, SStreamTaskExecRsp)
 
+  // Requests handled by SCHEDULER
+  TD_NEW_MSG_SEG(TDMT_SCH_MSG)
+  TD_DEF_MSG_TYPE(TDMT_SCH_LINK_BROKEN, "scheduler-link-broken", NULL, NULL)
+  
 #if defined(TD_MSG_NUMBER_)
   TDMT_MAX
 #endif
diff --git a/include/libs/catalog/catalog.h b/include/libs/catalog/catalog.h
index dd5f7fc104..9f0d4b11c2 100644
--- a/include/libs/catalog/catalog.h
+++ b/include/libs/catalog/catalog.h
@@ -112,7 +112,7 @@ int32_t catalogUpdateDBVgInfo(SCatalog* pCatalog, const char* dbName, uint64_t d
 
 int32_t catalogRemoveDB(SCatalog* pCatalog, const char* dbName, uint64_t dbId);
 
-int32_t catalogRemoveTableMeta(SCatalog* pCtg, SName* pTableName);
+int32_t catalogRemoveTableMeta(SCatalog* pCtg, const SName* pTableName);
 
 int32_t catalogRemoveStbMeta(SCatalog* pCtg, const char* dbFName, uint64_t dbId, const char* stbName, uint64_t suid);
 
diff --git a/include/libs/nodes/plannodes.h b/include/libs/nodes/plannodes.h
index 794e0ca85a..4d025eb9b7 100644
--- a/include/libs/nodes/plannodes.h
+++ b/include/libs/nodes/plannodes.h
@@ -48,6 +48,7 @@ typedef struct SScanLogicNode {
   uint8_t scanFlag;         // denotes reversed scan of data or not
   STimeWindow scanRange;
   SName tableName;
+  bool showRewrite;
 } SScanLogicNode;
 
 typedef struct SJoinLogicNode {
@@ -171,6 +172,8 @@ typedef SScanPhysiNode SStreamScanPhysiNode;
 typedef struct SSystemTableScanPhysiNode {
   SScanPhysiNode scan;
   SEpSet mgmtEpSet;
+  bool showRewrite;
+  int32_t accountId;
 } SSystemTableScanPhysiNode;
 
 typedef struct STableScanPhysiNode {
diff --git a/include/libs/parser/parser.h b/include/libs/parser/parser.h
index 2254298e5c..0747534721 100644
--- a/include/libs/parser/parser.h
+++ b/include/libs/parser/parser.h
@@ -54,6 +54,7 @@ typedef struct SQuery {
   int32_t msgType;
   SArray* pDbList;
   SArray* pTableList;
+  bool showRewrite;
 } SQuery;
 
 int32_t qParseQuerySql(SParseContext* pCxt, SQuery** pQuery);
diff --git a/include/libs/planner/planner.h b/include/libs/planner/planner.h
index 38b30ec01e..8db78fccf5 100644
--- a/include/libs/planner/planner.h
+++ b/include/libs/planner/planner.h
@@ -29,6 +29,7 @@ typedef struct SPlanContext {
   SNode* pAstRoot;
   bool topicQuery;
   bool streamQuery;
+  bool showRewrite;
 } SPlanContext;
 
 // Create the physical plan for the query, according to the AST.
diff --git a/include/libs/qcom/query.h b/include/libs/qcom/query.h
index 839feb7800..24953c6684 100644
--- a/include/libs/qcom/query.h
+++ b/include/libs/qcom/query.h
@@ -150,6 +150,8 @@ int32_t cleanupTaskQueue();
  */
 int32_t taosAsyncExec(__async_exec_fn_t execFn, void* execParam, int32_t* code);
 
+int32_t asyncSendMsgToServerExt(void* pTransporter, SEpSet* epSet, int64_t* pTransporterId, const SMsgSendInfo* pInfo, bool persistHandle, void *ctx);
+
 /**
  * Asynchronously send message to server, after the response received, the callback will be incured.
  *
diff --git a/include/libs/qworker/qworker.h b/include/libs/qworker/qworker.h
index 944ac97ddb..0846841cef 100644
--- a/include/libs/qworker/qworker.h
+++ b/include/libs/qworker/qworker.h
@@ -28,6 +28,7 @@ enum {
   NODE_TYPE_VNODE = 1,
   NODE_TYPE_QNODE,
   NODE_TYPE_SNODE,
+  NODE_TYPE_MNODE,
 };
 
 
diff --git a/include/libs/transport/trpc.h b/include/libs/transport/trpc.h
index 6112a77a12..8125de7647 100644
--- a/include/libs/transport/trpc.h
+++ b/include/libs/transport/trpc.h
@@ -52,8 +52,8 @@ typedef struct {
   char    user[TSDB_USER_LEN];
   SRpcMsg rpcMsg;
   int32_t rspLen;
-  void   *pRsp;
-  void   *pNode;
+  void *  pRsp;
+  void *  pNode;
 } SNodeMsg;
 
 typedef struct SRpcInit {
@@ -81,13 +81,21 @@ typedef struct SRpcInit {
 } SRpcInit;
 
 typedef struct {
-  void *  val;
-  int32_t len;
-  void (*freeFunc)(const void *arg);
+  void     *val;
+  int32_t (*clone)(void *src, void **dst);
+  void    (*freeFunc)(const void *arg);
 } SRpcCtxVal;
 
 typedef struct {
-  SHashObj *args;
+  int32_t   msgType;
+  void     *val;
+  int32_t (*clone)(void *src, void **dst);
+  void    (*freeFunc)(const void *arg);
+} SRpcBrokenlinkVal;
+
+typedef struct {
+  SHashObj *        args;
+  SRpcBrokenlinkVal brokenVal;
 } SRpcCtx;
 
 int32_t rpcInit();
diff --git a/include/util/tdef.h b/include/util/tdef.h
index fd8194e63e..655deb4625 100644
--- a/include/util/tdef.h
+++ b/include/util/tdef.h
@@ -109,6 +109,8 @@ extern const int32_t TYPE_BYTES[15];
 #define TSDB_INS_TABLE_USER_USERS             "user_users"
 #define TSDB_INS_TABLE_VGROUPS                "vgroups"
 
+#define TSDB_INS_USER_STABLES_DBNAME_COLID    2
+
 #define TSDB_TICK_PER_SECOND(precision)                      \
   ((int64_t)((precision) == TSDB_TIME_PRECISION_MILLI ? 1e3L \
                                                       : ((precision) == TSDB_TIME_PRECISION_MICRO ? 1e6L : 1e9L)))
diff --git a/source/client/src/clientEnv.c b/source/client/src/clientEnv.c
index f328f518ac..d9dcadbff0 100644
--- a/source/client/src/clientEnv.c
+++ b/source/client/src/clientEnv.c
@@ -192,6 +192,10 @@ static void doDestroyRequest(void *p) {
   doFreeReqResultInfo(&pRequest->body.resInfo);
   qDestroyQueryPlan(pRequest->body.pDag);
 
+  if (pRequest->body.queryJob != 0) {
+    schedulerFreeJob(pRequest->body.queryJob);
+  }
+
   if (pRequest->body.showInfo.pArray != NULL) {
     taosArrayDestroy(pRequest->body.showInfo.pArray);
   }
diff --git a/source/client/src/clientImpl.c b/source/client/src/clientImpl.c
index 0fa1391b6e..6e65a4267f 100644
--- a/source/client/src/clientImpl.c
+++ b/source/client/src/clientImpl.c
@@ -199,7 +199,8 @@ int32_t getPlan(SRequestObj* pRequest, SQuery* pQuery, SQueryPlan** pPlan, SArra
     .queryId = pRequest->requestId,
     .acctId = pRequest->pTscObj->acctId,
     .mgmtEpSet = getEpSet_s(&pRequest->pTscObj->pAppInfo->mgmtEp),
-    .pAstRoot = pQuery->pRoot
+    .pAstRoot = pQuery->pRoot,
+    .showRewrite = pQuery->showRewrite
   };
   int32_t  code = qCreateQueryPlan(&cxt, pPlan, pNodeList);
   if (code != 0) {
@@ -330,6 +331,8 @@ SRequestObj* execQuery(STscObj* pTscObj, const char* sql, int sqlLen) {
       pRequest->code = code;
       break;
     }
+
+    destroyRequest(pRequest);
   }
   
   return pRequest;
diff --git a/source/common/src/tmsg.c b/source/common/src/tmsg.c
index d7df3e115f..61d012ad97 100644
--- a/source/common/src/tmsg.c
+++ b/source/common/src/tmsg.c
@@ -2871,7 +2871,6 @@ int32_t tSerializeSSchedulerHbRsp(void *buf, int32_t bufLen, SSchedulerHbRsp *pR
   tCoderInit(&encoder, TD_LITTLE_ENDIAN, buf, bufLen, TD_ENCODER);
 
   if (tStartEncode(&encoder) < 0) return -1;
-  if (tEncodeU64(&encoder, pRsp->seqId) < 0) return -1;
   if (tEncodeI32(&encoder, pRsp->epId.nodeId) < 0) return -1;
   if (tEncodeU16(&encoder, pRsp->epId.ep.port) < 0) return -1;
   if (tEncodeCStr(&encoder, pRsp->epId.ep.fqdn) < 0) return -1;
@@ -2900,7 +2899,6 @@ int32_t tDeserializeSSchedulerHbRsp(void *buf, int32_t bufLen, SSchedulerHbRsp *
   tCoderInit(&decoder, TD_LITTLE_ENDIAN, buf, bufLen, TD_DECODER);
 
   if (tStartDecode(&decoder) < 0) return -1;
-  if (tDecodeU64(&decoder, &pRsp->seqId) < 0) return -1;
   if (tDecodeI32(&decoder, &pRsp->epId.nodeId) < 0) return -1;
   if (tDecodeU16(&decoder, &pRsp->epId.ep.port) < 0) return -1;
   if (tDecodeCStrTo(&decoder, pRsp->epId.ep.fqdn) < 0) return -1;
diff --git a/source/dnode/mgmt/container/src/dndInt.c b/source/dnode/mgmt/container/src/dndInt.c
index ab19415168..33d6bb0ee3 100644
--- a/source/dnode/mgmt/container/src/dndInt.c
+++ b/source/dnode/mgmt/container/src/dndInt.c
@@ -134,6 +134,7 @@ void dndProcessStartupReq(SDnode *pDnode, SRpcMsg *pReq) {
   dndGetStartup(pDnode, pStartup);
 
   dDebug("startup req is sent, step:%s desc:%s finished:%d", pStartup->name, pStartup->desc, pStartup->finished);
-  SRpcMsg rpcRsp = {.handle = pReq->handle, .pCont = pStartup, .contLen = sizeof(SStartupReq)};
+  SRpcMsg rpcRsp = {
+      .handle = pReq->handle, .pCont = pStartup, .contLen = sizeof(SStartupReq), .ahandle = pReq->ahandle};
   rpcSendResponse(&rpcRsp);
 }
diff --git a/source/dnode/mgmt/dnode/src/dmWorker.c b/source/dnode/mgmt/dnode/src/dmWorker.c
index be08aad7cb..d34a26436c 100644
--- a/source/dnode/mgmt/dnode/src/dmWorker.c
+++ b/source/dnode/mgmt/dnode/src/dmWorker.c
@@ -23,7 +23,7 @@
 
 static void *dmThreadRoutine(void *param) {
   SDnodeMgmt *pMgmt = param;
-  SDnode     *pDnode = pMgmt->pDnode;
+  SDnode *    pDnode = pMgmt->pDnode;
   int64_t     lastStatusTime = taosGetTimestampMs();
   int64_t     lastMonitorTime = lastStatusTime;
 
@@ -55,7 +55,7 @@ static void *dmThreadRoutine(void *param) {
 static void dmProcessQueue(SQueueInfo *pInfo, SNodeMsg *pMsg) {
   SDnodeMgmt *pMgmt = pInfo->ahandle;
 
-  SDnode  *pDnode = pMgmt->pDnode;
+  SDnode * pDnode = pMgmt->pDnode;
   SRpcMsg *pRpc = &pMsg->rpcMsg;
   int32_t  code = -1;
   dTrace("msg:%p, will be processed in dnode queue", pMsg);
diff --git a/source/dnode/mgmt/mnode/inc/mmInt.h b/source/dnode/mgmt/mnode/inc/mmInt.h
index d57088474f..cd4585048b 100644
--- a/source/dnode/mgmt/mnode/inc/mmInt.h
+++ b/source/dnode/mgmt/mnode/inc/mmInt.h
@@ -28,6 +28,7 @@ typedef struct SMnodeMgmt {
   SDnode       *pDnode;
   SMgmtWrapper *pWrapper;
   const char   *path;
+  SSingleWorker queryWorker;
   SSingleWorker readWorker;
   SSingleWorker writeWorker;
   SSingleWorker syncWorker;
@@ -57,11 +58,13 @@ void    mmStopWorker(SMnodeMgmt *pMgmt);
 int32_t mmProcessWriteMsg(SMnodeMgmt *pMgmt, SNodeMsg *pMsg);
 int32_t mmProcessSyncMsg(SMnodeMgmt *pMgmt, SNodeMsg *pMsg);
 int32_t mmProcessReadMsg(SMnodeMgmt *pMgmt, SNodeMsg *pMsg);
+int32_t mmProcessQueryMsg(SMnodeMgmt *pMgmt, SNodeMsg *pMsg);
 int32_t mmPutMsgToWriteQueue(SMgmtWrapper *pWrapper, SRpcMsg *pRpcMsg);
 int32_t mmPutMsgToReadQueue(SMgmtWrapper *pWrapper, SRpcMsg *pRpcMsg);
+int32_t mmPutMsgToQueryQueue(SMgmtWrapper *pWrapper, SRpcMsg *pRpc);
 
 #ifdef __cplusplus
 }
 #endif
 
-#endif /*_TD_DND_MNODE_INT_H_*/
\ No newline at end of file
+#endif /*_TD_DND_MNODE_INT_H_*/
diff --git a/source/dnode/mgmt/mnode/src/mmInt.c b/source/dnode/mgmt/mnode/src/mmInt.c
index cefa36ef10..61afcb11d1 100644
--- a/source/dnode/mgmt/mnode/src/mmInt.c
+++ b/source/dnode/mgmt/mnode/src/mmInt.c
@@ -45,7 +45,8 @@ static void mmInitOption(SMnodeMgmt *pMgmt, SMnodeOpt *pOption) {
 
   SMsgCb msgCb = {0};
   msgCb.pWrapper = pMgmt->pWrapper;
-  msgCb.queueFps[QUERY_QUEUE] = mmPutMsgToReadQueue;
+  msgCb.queueFps[QUERY_QUEUE] = mmPutMsgToQueryQueue;
+  msgCb.queueFps[READ_QUEUE] = mmPutMsgToReadQueue;
   msgCb.queueFps[WRITE_QUEUE] = mmPutMsgToWriteQueue;
   msgCb.sendReqFp = dndSendReqToDnode;
   msgCb.sendMnodeReqFp = dndSendReqToMnode;
@@ -258,4 +259,4 @@ int32_t mmMonitorMnodeInfo(SMgmtWrapper *pWrapper, SMonClusterInfo *pClusterInfo
                          SMonGrantInfo *pGrantInfo) {
   SMnodeMgmt *pMgmt = pWrapper->pMgmt;
   return mndGetMonitorInfo(pMgmt->pMnode, pClusterInfo, pVgroupInfo, pGrantInfo);
-}
\ No newline at end of file
+}
diff --git a/source/dnode/mgmt/mnode/src/mmMsg.c b/source/dnode/mgmt/mnode/src/mmMsg.c
index 1cae2220ad..d04077baf8 100644
--- a/source/dnode/mgmt/mnode/src/mmMsg.c
+++ b/source/dnode/mgmt/mnode/src/mmMsg.c
@@ -156,9 +156,10 @@ void mmInitMsgHandles(SMgmtWrapper *pWrapper) {
   dndSetMsgHandle(pWrapper, TDMT_VND_CREATE_SMA_RSP, (NodeMsgFp)mmProcessWriteMsg, VND_VGID);
   dndSetMsgHandle(pWrapper, TDMT_VND_DROP_SMA_RSP, (NodeMsgFp)mmProcessWriteMsg, VND_VGID);
 
-  dndSetMsgHandle(pWrapper, TDMT_VND_QUERY, (NodeMsgFp)mmProcessReadMsg, MND_VGID);
-  dndSetMsgHandle(pWrapper, TDMT_VND_QUERY_CONTINUE, (NodeMsgFp)mmProcessReadMsg, MND_VGID);
-  dndSetMsgHandle(pWrapper, TDMT_VND_FETCH, (NodeMsgFp)mmProcessReadMsg, MND_VGID);
-  dndSetMsgHandle(pWrapper, TDMT_VND_FETCH_RSP, (NodeMsgFp)mmProcessReadMsg, MND_VGID);
+  dndSetMsgHandle(pWrapper, TDMT_VND_QUERY, (NodeMsgFp)mmProcessQueryMsg, MND_VGID);
+  dndSetMsgHandle(pWrapper, TDMT_VND_QUERY_CONTINUE, (NodeMsgFp)mmProcessQueryMsg, MND_VGID);
+  dndSetMsgHandle(pWrapper, TDMT_VND_FETCH, (NodeMsgFp)mmProcessQueryMsg, MND_VGID);
+  dndSetMsgHandle(pWrapper, TDMT_VND_DROP_TASK, (NodeMsgFp)mmProcessQueryMsg, MND_VGID);
+  dndSetMsgHandle(pWrapper, TDMT_VND_QUERY_HEARTBEAT, (NodeMsgFp)mmProcessQueryMsg, MND_VGID);
 
 }
diff --git a/source/dnode/mgmt/mnode/src/mmWorker.c b/source/dnode/mgmt/mnode/src/mmWorker.c
index d6b150106d..27489b45d0 100644
--- a/source/dnode/mgmt/mnode/src/mmWorker.c
+++ b/source/dnode/mgmt/mnode/src/mmWorker.c
@@ -44,6 +44,30 @@ static void mmProcessQueue(SQueueInfo *pInfo, SNodeMsg *pMsg) {
   taosFreeQitem(pMsg);
 }
 
+static void mmProcessQueryQueue(SQueueInfo *pInfo, SNodeMsg *pMsg) {
+  SMnodeMgmt *pMgmt = pInfo->ahandle;
+
+  dTrace("msg:%p, will be processed in mnode queue", pMsg);
+  SRpcMsg *pRpc = &pMsg->rpcMsg;
+  int32_t  code = -1;
+
+  pMsg->pNode = pMgmt->pMnode;
+  code = mndProcessMsg(pMsg);
+
+  if (pRpc->msgType & 1U) {
+    if (pRpc->handle == NULL) return;
+    if (code != 0) {
+      SRpcMsg rsp = {.handle = pRpc->handle, .code = code, .ahandle = pRpc->ahandle};
+      dndSendRsp(pMgmt->pWrapper, &rsp);
+    }
+  }
+
+  dTrace("msg:%p, is freed, result:0x%04x:%s", pMsg, code & 0XFFFF, tstrerror(code));
+  rpcFreeCont(pRpc->pCont);
+  taosFreeQitem(pMsg);
+}
+
+
 static int32_t mmPutMsgToWorker(SMnodeMgmt *pMgmt, SSingleWorker *pWorker, SNodeMsg *pMsg) {
   dTrace("msg:%p, put into worker %s", pMsg, pWorker->name);
   return taosWriteQitem(pWorker->queue, pMsg);
@@ -61,6 +85,10 @@ int32_t mmProcessReadMsg(SMnodeMgmt *pMgmt, SNodeMsg *pMsg) {
   return mmPutMsgToWorker(pMgmt, &pMgmt->readWorker, pMsg);
 }
 
+int32_t mmProcessQueryMsg(SMnodeMgmt *pMgmt, SNodeMsg *pMsg) {
+  return mmPutMsgToWorker(pMgmt, &pMgmt->queryWorker, pMsg);
+}
+
 static int32_t mmPutRpcMsgToWorker(SMnodeMgmt *pMgmt, SSingleWorker *pWorker, SRpcMsg *pRpc) {
   SNodeMsg *pMsg = taosAllocateQitem(sizeof(SNodeMsg));
   if (pMsg == NULL) {
@@ -90,8 +118,20 @@ int32_t mmPutMsgToReadQueue(SMgmtWrapper *pWrapper, SRpcMsg *pRpc) {
   return mmPutRpcMsgToWorker(pMgmt, &pMgmt->readWorker, pRpc);
 }
 
+int32_t mmPutMsgToQueryQueue(SMgmtWrapper *pWrapper, SRpcMsg *pRpc) {
+  SMnodeMgmt *pMgmt = pWrapper->pMgmt;
+  return mmPutRpcMsgToWorker(pMgmt, &pMgmt->queryWorker, pRpc);
+}
+
+
 int32_t mmStartWorker(SMnodeMgmt *pMgmt) {
   SSingleWorkerCfg cfg = {.minNum = 0, .maxNum = 1, .name = "mnode-read", .fp = (FItem)mmProcessQueue, .param = pMgmt};
+  SSingleWorkerCfg queryCfg = {.minNum = 0, .maxNum = 1, .name = "mnode-query", .fp = (FItem)mmProcessQueryQueue, .param = pMgmt};
+
+  if (tSingleWorkerInit(&pMgmt->queryWorker, &queryCfg) != 0) {
+    dError("failed to start mnode-query worker since %s", terrstr());
+    return -1;
+  }
 
   if (tSingleWorkerInit(&pMgmt->readWorker, &cfg) != 0) {
     dError("failed to start mnode-read worker since %s", terrstr());
@@ -114,6 +154,7 @@ int32_t mmStartWorker(SMnodeMgmt *pMgmt) {
 
 void mmStopWorker(SMnodeMgmt *pMgmt) {
   tSingleWorkerCleanup(&pMgmt->readWorker);
+  tSingleWorkerCleanup(&pMgmt->queryWorker);
   tSingleWorkerCleanup(&pMgmt->writeWorker);
   tSingleWorkerCleanup(&pMgmt->syncWorker);
   dDebug("mnode workers are closed");
diff --git a/source/dnode/mgmt/vnode/src/vmWorker.c b/source/dnode/mgmt/vnode/src/vmWorker.c
index 4667ebc50d..e97d6e7f11 100644
--- a/source/dnode/mgmt/vnode/src/vmWorker.c
+++ b/source/dnode/mgmt/vnode/src/vmWorker.c
@@ -165,8 +165,8 @@ static int32_t vmPutNodeMsgToQueue(SVnodesMgmt *pMgmt, SNodeMsg *pMsg, EQueueTyp
   int32_t  code = -1;
 
   SMsgHead *pHead = pRpc->pCont;
-  pHead->contLen = htonl(pHead->contLen);
-  pHead->vgId = htonl(pHead->vgId);
+  pHead->contLen = ntohl(pHead->contLen);
+  pHead->vgId = ntohl(pHead->vgId);
 
   SVnodeObj *pVnode = vmAcquireVnode(pMgmt, pHead->vgId);
   if (pVnode == NULL) {
diff --git a/source/dnode/mnode/impl/CMakeLists.txt b/source/dnode/mnode/impl/CMakeLists.txt
index 6cc9fae079..e91c851be7 100644
--- a/source/dnode/mnode/impl/CMakeLists.txt
+++ b/source/dnode/mnode/impl/CMakeLists.txt
@@ -6,7 +6,7 @@ target_include_directories(
     PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/inc"
 )
 target_link_libraries(
-    mnode scheduler sdb wal transport cjson sync monitor stream parser
+    mnode scheduler sdb wal transport cjson sync monitor executor qworker stream parser
 )
 
 if(${BUILD_TEST})
diff --git a/source/dnode/mnode/impl/inc/mndInt.h b/source/dnode/mnode/impl/inc/mndInt.h
index 20e85973be..f89e9d8fe0 100644
--- a/source/dnode/mnode/impl/inc/mndInt.h
+++ b/source/dnode/mnode/impl/inc/mndInt.h
@@ -59,6 +59,8 @@ typedef struct SMnodeLoad {
   int64_t compStorage;
 } SMnodeLoad;
 
+typedef struct SQWorkerMgmt SQHandle;
+
 typedef struct {
   const char  *name;
   MndInitFp    initFp;
@@ -112,6 +114,7 @@ typedef struct SMnode {
   SSdb             *pSdb;
   SMgmtWrapper     *pWrapper;
   SArray           *pSteps;
+  SQHandle         *pQuery;
   SShowMgmt         showMgmt;
   SProfileMgmt      profileMgmt;
   STelemMgmt        telemMgmt;
@@ -119,7 +122,7 @@ typedef struct SMnode {
   SHashObj         *infosMeta;
   SGrantInfo        grant;
   MndMsgFp          msgFp[TDMT_MAX];
-  SMsgCb            msgCb;
+  SMsgCb            msgCb;  
 } SMnode;
 
 void    mndSetMsgHandle(SMnode *pMnode, tmsg_t msgType, MndMsgFp fp);
diff --git a/source/dnode/mnode/impl/inc/mndQuery.h b/source/dnode/mnode/impl/inc/mndQuery.h
new file mode 100644
index 0000000000..7fab80de77
--- /dev/null
+++ b/source/dnode/mnode/impl/inc/mndQuery.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _TD_MND_QUERY_H_
+#define _TD_MND_QUERY_H_
+
+#include "mndInt.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int32_t  mndInitQuery(SMnode *pMnode);
+void     mndCleanupQuery(SMnode *pMnode);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /*_TD_MND_QUERY_H_*/
diff --git a/source/dnode/mnode/impl/src/mndDb.c b/source/dnode/mnode/impl/src/mndDb.c
index c556cfc71e..05c7d79a1a 100644
--- a/source/dnode/mnode/impl/src/mndDb.c
+++ b/source/dnode/mnode/impl/src/mndDb.c
@@ -1034,7 +1034,9 @@ static int32_t mndProcessUseDbReq(SNodeMsg *pReq) {
       usedbRsp.vgVersion = usedbReq.vgVersion;
       code = 0;
     }
-    usedbRsp.vgNum = taosArrayGetSize(usedbRsp.pVgroupInfos);    
+    usedbRsp.vgNum = taosArrayGetSize(usedbRsp.pVgroupInfos);  
+
+    // no jump, need to construct rsp
   } else {
     pDb = mndAcquireDb(pMnode, usedbReq.db);
     if (pDb == NULL) {
diff --git a/source/dnode/mnode/impl/src/mndInfoSchema.c b/source/dnode/mnode/impl/src/mndInfoSchema.c
index 5f369e7088..c9b69bc161 100644
--- a/source/dnode/mnode/impl/src/mndInfoSchema.c
+++ b/source/dnode/mnode/impl/src/mndInfoSchema.c
@@ -19,6 +19,7 @@
 #define SYSTABLE_SCH_TABLE_NAME_LEN ((TSDB_TABLE_NAME_LEN - 1) + VARSTR_HEADER_SIZE)
 #define SYSTABLE_SCH_DB_NAME_LEN    ((TSDB_DB_NAME_LEN - 1) + VARSTR_HEADER_SIZE)
 
+//!!!! Note: only APPEND columns in below tables, NO insert !!!!
 static const SInfosTableSchema dnodesSchema[] = {{.name = "id",             .bytes = 2,   .type = TSDB_DATA_TYPE_SMALLINT},
                                                  {.name = "endpoint",       .bytes = TSDB_EP_LEN + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_BINARY},
                                                  {.name = "vnodes",         .bytes = 2,   .type = TSDB_DATA_TYPE_SMALLINT},
diff --git a/source/dnode/mnode/impl/src/mndQuery.c b/source/dnode/mnode/impl/src/mndQuery.c
new file mode 100644
index 0000000000..e93a0d9b17
--- /dev/null
+++ b/source/dnode/mnode/impl/src/mndQuery.c
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "mndQuery.h"
+#include "mndMnode.h"
+#include "executor.h"
+#include "qworker.h"
+
+int32_t mndProcessQueryMsg(SNodeMsg *pReq) {
+  mTrace("message in query queue is processing");
+  SMnode *pMnode = pReq->pNode;
+  SReadHandle handle = {0};
+
+  switch (pReq->rpcMsg.msgType) {
+    case TDMT_VND_QUERY:
+      return qWorkerProcessQueryMsg(&handle, pMnode->pQuery, &pReq->rpcMsg);
+    case TDMT_VND_QUERY_CONTINUE:
+      return qWorkerProcessCQueryMsg(&handle, pMnode->pQuery, &pReq->rpcMsg);
+    default:
+      mError("unknown msg type:%d in query queue", pReq->rpcMsg.msgType);
+      return TSDB_CODE_VND_APP_ERROR;
+  }
+}
+
+int32_t mndProcessFetchMsg(SNodeMsg *pReq) {
+  mTrace("message in fetch queue is processing");
+  SMnode *pMnode = pReq->pNode;
+  
+  switch (pReq->rpcMsg.msgType) {
+    case TDMT_VND_FETCH:
+      return qWorkerProcessFetchMsg(pMnode, pMnode->pQuery, &pReq->rpcMsg);
+    case TDMT_VND_DROP_TASK:
+      return qWorkerProcessDropMsg(pMnode, pMnode->pQuery, &pReq->rpcMsg);
+    case TDMT_VND_QUERY_HEARTBEAT:
+      return qWorkerProcessHbMsg(pMnode, pMnode->pQuery, &pReq->rpcMsg);
+    default:
+      mError("unknown msg type:%d in fetch queue", pReq->rpcMsg.msgType);
+      return TSDB_CODE_VND_APP_ERROR;
+  }
+}
+
+int32_t mndInitQuery(SMnode *pMnode) {
+  int32_t code = qWorkerInit(NODE_TYPE_MNODE, MND_VGID, NULL, (void **)&pMnode->pQuery, &pMnode->msgCb);
+  if (code) {
+    return code;
+  }
+
+  mndSetMsgHandle(pMnode, TDMT_VND_QUERY, mndProcessQueryMsg);
+  mndSetMsgHandle(pMnode, TDMT_VND_QUERY_CONTINUE, mndProcessQueryMsg);
+  mndSetMsgHandle(pMnode, TDMT_VND_FETCH, mndProcessFetchMsg);
+  mndSetMsgHandle(pMnode, TDMT_VND_DROP_TASK, mndProcessFetchMsg);
+  mndSetMsgHandle(pMnode, TDMT_VND_QUERY_HEARTBEAT, mndProcessFetchMsg);
+
+  return 0;
+}
+
+void mndCleanupQuery(SMnode *pMnode) { qWorkerDestroy((void **)&pMnode->pQuery); }
+
diff --git a/source/dnode/mnode/impl/src/mndShow.c b/source/dnode/mnode/impl/src/mndShow.c
index a830ee7104..dff918f135 100644
--- a/source/dnode/mnode/impl/src/mndShow.c
+++ b/source/dnode/mnode/impl/src/mndShow.c
@@ -357,6 +357,13 @@ static int32_t mndProcessRetrieveSysTableReq(SNodeMsg *pReq) {
   // if free flag is set, client wants to clean the resources
   if ((retrieveReq.free & TSDB_QUERY_TYPE_FREE_RESOURCE) != TSDB_QUERY_TYPE_FREE_RESOURCE) {
     rowsRead = (*retrieveFp)(pReq, (SShowObj*) pShow, pRsp->data, rowsToRead);
+    if (rowsRead < 0) {
+      terrno = rowsRead;
+      rpcFreeCont(pRsp);
+      mDebug("show:0x%" PRIx64 ", retrieve completed", pShow->id);
+      mndReleaseShowObj((SShowObj*) pShow, true);
+      return -1;
+    }
   }
 
   mDebug("show:0x%" PRIx64 ", stop retrieve data, rowsRead:%d rowsToRead:%d", pShow->id, rowsRead, rowsToRead);
diff --git a/source/dnode/mnode/impl/src/mndStb.c b/source/dnode/mnode/impl/src/mndStb.c
index acf45a31d9..fdd03be710 100644
--- a/source/dnode/mnode/impl/src/mndStb.c
+++ b/source/dnode/mnode/impl/src/mndStb.c
@@ -1613,7 +1613,7 @@ static int32_t mndRetrieveStb(SNodeMsg *pReq, SShowObj *pShow, char *data, int32
   SDbObj* pDb = NULL;
   if (strlen(pShow->db) > 0) {
     pDb = mndAcquireDb(pMnode, pShow->db);
-    if (pDb == NULL) return 0;
+    if (pDb == NULL) return terrno;
   }
 
   while (numOfRows < rows) {
diff --git a/source/dnode/mnode/impl/src/mnode.c b/source/dnode/mnode/impl/src/mnode.c
index 08f0b20d31..67b7d6dd45 100644
--- a/source/dnode/mnode/impl/src/mnode.c
+++ b/source/dnode/mnode/impl/src/mnode.c
@@ -39,6 +39,7 @@
 #include "mndTrans.h"
 #include "mndUser.h"
 #include "mndVgroup.h"
+#include "mndQuery.h"
 
 #define MQ_TIMER_MS    3000
 #define TRNAS_TIMER_MS 6000
@@ -79,7 +80,7 @@ static void mndCalMqRebalance(void *param, void *tmrId) {
         .pCont = pReq,
         .contLen = contLen,
     };
-    tmsgPutToQueue(&pMnode->msgCb, QUERY_QUEUE, &rpcMsg);
+    tmsgPutToQueue(&pMnode->msgCb, READ_QUEUE, &rpcMsg);
   }
 
   taosTmrReset(mndCalMqRebalance, MQ_TIMER_MS, pMnode, pMnode->timer, &pMnode->mqTimer);
@@ -91,7 +92,7 @@ static void mndPullupTelem(void *param, void *tmrId) {
     int32_t contLen = 0;
     void   *pReq = mndBuildTimerMsg(&contLen);
     SRpcMsg rpcMsg = {.msgType = TDMT_MND_TELEM_TIMER, .pCont = pReq, .contLen = contLen};
-    tmsgPutToQueue(&pMnode->msgCb, QUERY_QUEUE, &rpcMsg);
+    tmsgPutToQueue(&pMnode->msgCb, READ_QUEUE, &rpcMsg);
   }
 
   taosTmrReset(mndPullupTelem, TELEM_TIMER_MS, pMnode, pMnode->timer, &pMnode->telemTimer);
@@ -217,6 +218,7 @@ static int32_t mndInitSteps(SMnode *pMnode) {
   // if (mndAllocStep(pMnode, "mnode-timer", mndInitTimer, NULL) != 0) return -1;
   if (mndAllocStep(pMnode, "mnode-profile", mndInitProfile, mndCleanupProfile) != 0) return -1;
   if (mndAllocStep(pMnode, "mnode-show", mndInitShow, mndCleanupShow) != 0) return -1;
+  if (mndAllocStep(pMnode, "mnode-query", mndInitQuery, mndCleanupQuery) != 0) return -1;
   if (mndAllocStep(pMnode, "mnode-sync", mndInitSync, mndCleanupSync) != 0) return -1;
   if (mndAllocStep(pMnode, "mnode-telem", mndInitTelem, mndCleanupTelem) != 0) return -1;
   if (mndAllocStep(pMnode, "mnode-timer", NULL, mndCleanupTimer) != 0) return -1;
diff --git a/source/dnode/vnode/src/vnd/vnodeQuery.c b/source/dnode/vnode/src/vnd/vnodeQuery.c
index 6b5eb5bd6f..1db17f37cb 100644
--- a/source/dnode/vnode/src/vnd/vnodeQuery.c
+++ b/source/dnode/vnode/src/vnd/vnodeQuery.c
@@ -31,9 +31,8 @@ int vnodeProcessQueryMsg(SVnode *pVnode, SRpcMsg *pMsg) {
   SReadHandle handle = {.reader = pVnode->pTsdb, .meta = pVnode->pMeta, .config = &pVnode->config};
 
   switch (pMsg->msgType) {
-    case TDMT_VND_QUERY: {
+    case TDMT_VND_QUERY:
       return qWorkerProcessQueryMsg(&handle, pVnode->pQuery, pMsg);
-    }
     case TDMT_VND_QUERY_CONTINUE:
       return qWorkerProcessCQueryMsg(&handle, pVnode->pQuery, pMsg);
     default:
@@ -205,7 +204,7 @@ _exit:
 
   rpcSendResponse(&rpcMsg);
 
-  return code;
+  return TSDB_CODE_SUCCESS;
 }
 
 static void freeItemHelper(void *pItem) {
diff --git a/source/libs/catalog/src/catalog.c b/source/libs/catalog/src/catalog.c
index 7bbff05b4b..6eab0d280b 100644
--- a/source/libs/catalog/src/catalog.c
+++ b/source/libs/catalog/src/catalog.c
@@ -406,9 +406,9 @@ _return:
 }
 
 
-int32_t ctgPushRmStbMsgInQueue(SCatalog* pCtg, const char *dbFName, int64_t dbId, const char *stbName, uint64_t suid) {
+int32_t ctgPushRmStbMsgInQueue(SCatalog* pCtg, const char *dbFName, int64_t dbId, const char *stbName, uint64_t suid, bool syncReq) {
   int32_t code = 0;
-  SCtgMetaAction action= {.act = CTG_ACT_REMOVE_STB};
+  SCtgMetaAction action= {.act = CTG_ACT_REMOVE_STB, .syncReq = syncReq};
   SCtgRemoveStbMsg *msg = taosMemoryMalloc(sizeof(SCtgRemoveStbMsg));
   if (NULL == msg) {
     ctgError("malloc %d failed", (int32_t)sizeof(SCtgRemoveStbMsg));
@@ -435,9 +435,9 @@ _return:
 
 
 
-int32_t ctgPushRmTblMsgInQueue(SCatalog* pCtg, const char *dbFName, int64_t dbId, const char *tbName) {
+int32_t ctgPushRmTblMsgInQueue(SCatalog* pCtg, const char *dbFName, int64_t dbId, const char *tbName, bool syncReq) {
   int32_t code = 0;
-  SCtgMetaAction action= {.act = CTG_ACT_REMOVE_TBL};
+  SCtgMetaAction action= {.act = CTG_ACT_REMOVE_TBL, .syncReq = syncReq};
   SCtgRemoveTblMsg *msg = taosMemoryMalloc(sizeof(SCtgRemoveTblMsg));
   if (NULL == msg) {
     ctgError("malloc %d failed", (int32_t)sizeof(SCtgRemoveTblMsg));
@@ -496,7 +496,7 @@ _return:
 
 int32_t ctgPushUpdateTblMsgInQueue(SCatalog* pCtg, STableMetaOutput *output, bool syncReq) {
   int32_t code = 0;
-  SCtgMetaAction action= {.act = CTG_ACT_UPDATE_TBL};
+  SCtgMetaAction action= {.act = CTG_ACT_UPDATE_TBL, .syncReq = syncReq};
   SCtgUpdateTblMsg *msg = taosMemoryMalloc(sizeof(SCtgUpdateTblMsg));
   if (NULL == msg) {
     ctgError("malloc %d failed", (int32_t)sizeof(SCtgUpdateTblMsg));
@@ -1843,6 +1843,7 @@ int32_t ctgRefreshTblMeta(SCatalog* pCtg, void *pTrans, const SEpSet* pMgmtEps,
 
   if (CTG_IS_META_NULL(output->metaType)) {
     ctgError("no tbmeta got, tbNmae:%s", tNameGetTableName(pTableName));
+    catalogRemoveTableMeta(pCtg, pTableName);
     CTG_ERR_JRET(CTG_ERR_CODE_TABLE_NOT_EXIST);
   }
 
@@ -1951,9 +1952,9 @@ _return:
     }
 
     if (TSDB_SUPER_TABLE == tbType) {
-      ctgPushRmStbMsgInQueue(pCtg, dbFName, dbId, pTableName->tname, suid);
+      ctgPushRmStbMsgInQueue(pCtg, dbFName, dbId, pTableName->tname, suid, false);
     } else {
-      ctgPushRmTblMsgInQueue(pCtg, dbFName, dbId, pTableName->tname);
+      ctgPushRmTblMsgInQueue(pCtg, dbFName, dbId, pTableName->tname, false);
     }
   }
 
@@ -2534,7 +2535,7 @@ int32_t catalogUpdateVgEpSet(SCatalog* pCtg, const char* dbFName, int32_t vgId,
 
 }
 
-int32_t catalogRemoveTableMeta(SCatalog* pCtg, SName* pTableName) {
+int32_t catalogRemoveTableMeta(SCatalog* pCtg, const SName* pTableName) {
   CTG_API_ENTER();
 
   int32_t code = 0;
@@ -2561,9 +2562,9 @@ int32_t catalogRemoveTableMeta(SCatalog* pCtg, SName* pTableName) {
   tNameGetFullDbName(pTableName, dbFName);
   
   if (TSDB_SUPER_TABLE == tblMeta->tableType) {
-    CTG_ERR_JRET(ctgPushRmStbMsgInQueue(pCtg, dbFName, dbId, pTableName->tname, tblMeta->suid));
+    CTG_ERR_JRET(ctgPushRmStbMsgInQueue(pCtg, dbFName, dbId, pTableName->tname, tblMeta->suid, true));
   } else {
-    CTG_ERR_JRET(ctgPushRmTblMsgInQueue(pCtg, dbFName, dbId, pTableName->tname));
+    CTG_ERR_JRET(ctgPushRmTblMsgInQueue(pCtg, dbFName, dbId, pTableName->tname, true));
   }
 
  
@@ -2588,7 +2589,7 @@ int32_t catalogRemoveStbMeta(SCatalog* pCtg, const char* dbFName, uint64_t dbId,
     CTG_API_LEAVE(TSDB_CODE_SUCCESS);
   }
 
-  CTG_ERR_JRET(ctgPushRmStbMsgInQueue(pCtg, dbFName, dbId, stbName, suid));
+  CTG_ERR_JRET(ctgPushRmStbMsgInQueue(pCtg, dbFName, dbId, stbName, suid, true));
 
   CTG_API_LEAVE(TSDB_CODE_SUCCESS);
   
diff --git a/source/libs/executor/inc/executorimpl.h b/source/libs/executor/inc/executorimpl.h
index c582873315..ead830394e 100644
--- a/source/libs/executor/inc/executorimpl.h
+++ b/source/libs/executor/inc/executorimpl.h
@@ -449,6 +449,8 @@ typedef struct SSysTableScanInfo {
   SEpSet              epSet;
   tsem_t              ready;
 
+  int32_t             accountId;
+  bool                showRewrite;
   SNode*              pCondition; // db_name filter condition, to discard data that are not in current database
   void               *pCur;       // cursor for iterate the local table meta store.
   SArray             *scanCols;   // SArray<int16_t> scan column id list
@@ -655,7 +657,7 @@ SOperatorInfo* createProjectOperatorInfo(SOperatorInfo* downstream, SExprInfo* p
 SOperatorInfo* createOrderOperatorInfo(SOperatorInfo* downstream, SExprInfo* pExprInfo, int32_t numOfCols, SArray* pOrderVal, SExecTaskInfo* pTaskInfo);
 SOperatorInfo* createSortedMergeOperatorInfo(SOperatorInfo** downstream, int32_t numOfDownstream, SExprInfo* pExprInfo, int32_t num, SArray* pOrderVal, SArray* pGroupInfo, SExecTaskInfo* pTaskInfo);
 SOperatorInfo* createSysTableScanOperatorInfo(void* pSysTableReadHandle, SSDataBlock* pResBlock, const SName* pName,
-                                              SNode* pCondition, SEpSet epset, SArray* colList, SExecTaskInfo* pTaskInfo);
+                                              SNode* pCondition, SEpSet epset, SArray* colList, SExecTaskInfo* pTaskInfo, bool showRewrite, int32_t accountId);
 SOperatorInfo* createLimitOperatorInfo(SOperatorInfo* downstream, SLimit* pLimit, SExecTaskInfo* pTaskInfo);
 
 SOperatorInfo* createIntervalOperatorInfo(SOperatorInfo* downstream, SExprInfo* pExprInfo, int32_t numOfCols, SSDataBlock* pResBlock, SInterval* pInterval,
diff --git a/source/libs/executor/src/executorimpl.c b/source/libs/executor/src/executorimpl.c
index fc0535358b..4f7f3d2d7e 100644
--- a/source/libs/executor/src/executorimpl.c
+++ b/source/libs/executor/src/executorimpl.c
@@ -5489,7 +5489,8 @@ SOperatorInfo* createStreamScanOperatorInfo(void *streamReadHandle, SSDataBlock*
 }
 
 static int32_t loadSysTableContentCb(void* param, const SDataBuf* pMsg, int32_t code) {
-  SSysTableScanInfo* pScanResInfo = (SSysTableScanInfo*) param;
+  SOperatorInfo* operator = (SOperatorInfo *)param;
+  SSysTableScanInfo* pScanResInfo = (SSysTableScanInfo *)operator->info;
   if (TSDB_CODE_SUCCESS == code) {
     pScanResInfo->pRsp = pMsg->pData;
 
@@ -5498,6 +5499,8 @@ static int32_t loadSysTableContentCb(void* param, const SDataBuf* pMsg, int32_t
     pRsp->useconds  = htobe64(pRsp->useconds);
     pRsp->handle    = htobe64(pRsp->handle);
     pRsp->compLen   = htonl(pRsp->compLen);
+  } else {
+    operator->pTaskInfo->code = code;
   }
 
   tsem_post(&pScanResInfo->ready);
@@ -5544,6 +5547,64 @@ static SSDataBlock* doFilterResult(SSysTableScanInfo* pInfo) {
   return pInfo->pRes->info.rows == 0? NULL:pInfo->pRes;
 }
 
+EDealRes getDBNameFromConditionWalker(SNode* pNode, void* pContext) {
+  int32_t code = TSDB_CODE_SUCCESS;
+  ENodeType nType = nodeType(pNode);
+
+  switch (nType) {
+    case QUERY_NODE_OPERATOR: {
+      SOperatorNode *node = (SOperatorNode *)pNode;
+
+      if (OP_TYPE_EQUAL == node->opType) {
+        *(int32_t *)pContext = 1;      
+        return DEAL_RES_CONTINUE;
+      }
+
+      *(int32_t *)pContext = 0;      
+
+      return DEAL_RES_IGNORE_CHILD;
+    }
+    case QUERY_NODE_COLUMN: {
+      if (1 != *(int32_t *)pContext) {
+        return DEAL_RES_CONTINUE;
+      }
+      
+      SColumnNode *node = (SColumnNode *)pNode;
+      if (TSDB_INS_USER_STABLES_DBNAME_COLID == node->colId) {
+        *(int32_t *)pContext = 2;      
+        return DEAL_RES_CONTINUE;
+      }
+
+      *(int32_t *)pContext = 0;  
+      return DEAL_RES_CONTINUE;
+    }
+    case QUERY_NODE_VALUE: {
+      if (2 != *(int32_t *)pContext) {
+        return DEAL_RES_CONTINUE;
+      }
+
+      SValueNode *node = (SValueNode *)pNode;
+      char *dbName = nodesGetValueFromNode(node);
+      strncpy(pContext, varDataVal(dbName), varDataLen(dbName)); 
+      *((char *)pContext + varDataLen(dbName)) = 0;
+      return DEAL_RES_ERROR;  // stop walk
+    }
+    default:
+      break;
+  }
+
+  return DEAL_RES_CONTINUE;
+}
+
+
+void getDBNameFromCondition(SNode *pCondition, char *dbName) {
+  if (NULL == pCondition) {
+    return;
+  }
+
+  nodesWalkNode(pCondition, getDBNameFromConditionWalker, dbName);
+}
+
 static SSDataBlock* doSysTableScan(SOperatorInfo *pOperator, bool* newgroup) {
 // build message and send to mnode to fetch the content of system tables.
   SExecTaskInfo* pTaskInfo = pOperator->pTaskInfo;
@@ -5600,6 +5661,11 @@ static SSDataBlock* doSysTableScan(SOperatorInfo *pOperator, bool* newgroup) {
 
     pInfo->req.type = pInfo->type;
     strncpy(pInfo->req.tb, tNameGetTableName(&pInfo->name), tListLen(pInfo->req.tb));
+    if (pInfo->showRewrite) {
+      char dbName[TSDB_DB_NAME_LEN] = {0};
+      getDBNameFromCondition(pInfo->pCondition, dbName);
+      sprintf(pInfo->req.db, "%d.%s", pInfo->accountId, dbName);
+    }
 
     int32_t contLen = tSerializeSRetrieveTableReq(NULL, 0, &pInfo->req);
     char* buf1 = taosMemoryCalloc(1, contLen);
@@ -5613,7 +5679,7 @@ static SSDataBlock* doSysTableScan(SOperatorInfo *pOperator, bool* newgroup) {
       return NULL;
     }
 
-    pMsgSendInfo->param = pInfo;
+    pMsgSendInfo->param = pOperator;
     pMsgSendInfo->msgInfo.pData = buf1;
     pMsgSendInfo->msgInfo.len = contLen;
     pMsgSendInfo->msgType = TDMT_MND_SYSTABLE_RETRIEVE;
@@ -5623,6 +5689,10 @@ static SSDataBlock* doSysTableScan(SOperatorInfo *pOperator, bool* newgroup) {
     int32_t code = asyncSendMsgToServer(pInfo->pTransporter, &pInfo->epSet, &transporterId, pMsgSendInfo);
     tsem_wait(&pInfo->ready);
 
+    if (pTaskInfo->code) {
+      return NULL;
+    }
+
     SRetrieveMetaTableRsp* pRsp = pInfo->pRsp;
     pInfo->req.showId = pRsp->handle;
 
@@ -5644,7 +5714,7 @@ static SSDataBlock* doSysTableScan(SOperatorInfo *pOperator, bool* newgroup) {
 }
 
 SOperatorInfo* createSysTableScanOperatorInfo(void* pSysTableReadHandle, SSDataBlock* pResBlock, const SName* pName,
-                                              SNode* pCondition, SEpSet epset, SArray* colList, SExecTaskInfo* pTaskInfo) {
+                                              SNode* pCondition, SEpSet epset, SArray* colList, SExecTaskInfo* pTaskInfo, bool showRewrite, int32_t accountId) {
   SSysTableScanInfo* pInfo = taosMemoryCalloc(1, sizeof(SSysTableScanInfo));
   SOperatorInfo* pOperator = taosMemoryCalloc(1, sizeof(SOperatorInfo));
   if (pInfo == NULL || pOperator == NULL) {
@@ -5654,10 +5724,12 @@ SOperatorInfo* createSysTableScanOperatorInfo(void* pSysTableReadHandle, SSDataB
     return NULL;
   }
 
-  pInfo->pRes       = pResBlock;
-  pInfo->capacity   = 4096;
-  pInfo->pCondition = pCondition;
-  pInfo->scanCols   = colList;
+  pInfo->accountId   = accountId;
+  pInfo->showRewrite = showRewrite;
+  pInfo->pRes        = pResBlock;
+  pInfo->capacity    = 4096;
+  pInfo->pCondition  = pCondition;
+  pInfo->scanCols    = colList;
 
   // TODO remove it
   int32_t tableType = 0;
@@ -8530,7 +8602,8 @@ SOperatorInfo* doCreateOperatorTreeNode(SPhysiNode* pPhyNode, SExecTaskInfo* pTa
       SArray* colList = extractScanColumnId(pScanNode->pScanCols);
 
       SOperatorInfo* pOperator = createSysTableScanOperatorInfo(pHandle->meta, pResBlock, &pScanNode->tableName,
-                                                                pScanNode->node.pConditions, pSysScanPhyNode->mgmtEpSet, colList, pTaskInfo);
+                                                                pScanNode->node.pConditions, pSysScanPhyNode->mgmtEpSet, 
+                                                                colList, pTaskInfo, pSysScanPhyNode->showRewrite, pSysScanPhyNode->accountId);
       return pOperator;
     } else {
       ASSERT(0);
diff --git a/source/libs/nodes/src/nodesCloneFuncs.c b/source/libs/nodes/src/nodesCloneFuncs.c
index 078f3ab3e6..a9660c8573 100644
--- a/source/libs/nodes/src/nodesCloneFuncs.c
+++ b/source/libs/nodes/src/nodesCloneFuncs.c
@@ -237,6 +237,7 @@ static SNode* logicScanCopy(const SScanLogicNode* pSrc, SScanLogicNode* pDst) {
   COPY_SCALAR_FIELD(scanFlag);
   COPY_SCALAR_FIELD(scanRange);
   COPY_SCALAR_FIELD(tableName);
+  COPY_SCALAR_FIELD(showRewrite);
   return (SNode*)pDst;
 }
 
diff --git a/source/libs/nodes/src/nodesCodeFuncs.c b/source/libs/nodes/src/nodesCodeFuncs.c
index 1acc3c51c5..d7caf6e511 100644
--- a/source/libs/nodes/src/nodesCodeFuncs.c
+++ b/source/libs/nodes/src/nodesCodeFuncs.c
@@ -764,6 +764,8 @@ static int32_t jsonToEpSet(const SJson* pJson, void* pObj) {
 }
 
 static const char* jkSysTableScanPhysiPlanMnodeEpSet = "MnodeEpSet";
+static const char* jkSysTableScanPhysiPlanShowRewrite = "ShowRewrite";
+static const char* jkSysTableScanPhysiPlanAccountId = "AccountId";
 
 static int32_t physiSysTableScanNodeToJson(const void* pObj, SJson* pJson) {
   const SSystemTableScanPhysiNode* pNode = (const SSystemTableScanPhysiNode*)pObj;
@@ -772,6 +774,12 @@ static int32_t physiSysTableScanNodeToJson(const void* pObj, SJson* pJson) {
   if (TSDB_CODE_SUCCESS == code) {
     code = tjsonAddObject(pJson, jkSysTableScanPhysiPlanMnodeEpSet, epSetToJson, &pNode->mgmtEpSet);
   }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddBoolToObject(pJson, jkSysTableScanPhysiPlanShowRewrite, pNode->showRewrite);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddIntegerToObject(pJson, jkSysTableScanPhysiPlanAccountId, pNode->accountId);
+  }
 
   return code;
 }
@@ -783,6 +791,12 @@ static int32_t jsonToPhysiSysTableScanNode(const SJson* pJson, void* pObj) {
   if (TSDB_CODE_SUCCESS == code) {
     code = tjsonToObject(pJson, jkSysTableScanPhysiPlanMnodeEpSet, jsonToEpSet, &pNode->mgmtEpSet);
   }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetBoolValue(pJson, jkSysTableScanPhysiPlanShowRewrite, &pNode->showRewrite);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetNumberValue(pJson, jkSysTableScanPhysiPlanAccountId, pNode->accountId);
+  }
 
   return code;
 }
diff --git a/source/libs/parser/src/parTranslater.c b/source/libs/parser/src/parTranslater.c
index 2d1882245d..1c721f3caf 100644
--- a/source/libs/parser/src/parTranslater.c
+++ b/source/libs/parser/src/parTranslater.c
@@ -84,12 +84,18 @@ static SName* toName(int32_t acctId, const char* pDbName, const char* pTableName
   return pName;
 }
 
-static int32_t collectUseDatabase(const char* pFullDbName, SHashObj* pDbs) {
+static int32_t collectUseDatabaseImpl(const char* pFullDbName, SHashObj* pDbs) {
   SFullDatabaseName name = {0};
   strcpy(name.fullDbName, pFullDbName);
   return taosHashPut(pDbs, pFullDbName, strlen(pFullDbName), &name, sizeof(SFullDatabaseName));
 }
 
+static int32_t collectUseDatabase(const SName* pName, SHashObj* pDbs) {
+  char dbFName[TSDB_DB_FNAME_LEN] = {0};
+  tNameGetFullDbName(pName, dbFName);
+  return collectUseDatabaseImpl(dbFName, pDbs);
+}
+
 static int32_t collectUseTable(const SName* pName, SHashObj* pDbs) {
   char fullName[TSDB_TABLE_FNAME_LEN];
   tNameExtractFullName(pName, fullName);
@@ -98,7 +104,10 @@ static int32_t collectUseTable(const SName* pName, SHashObj* pDbs) {
 
 static int32_t getTableMetaImpl(STranslateContext* pCxt, const SName* pName, STableMeta** pMeta) {
   SParseContext* pParCxt = pCxt->pParseCxt;
-  int32_t code = collectUseTable(pName, pCxt->pTables);
+  int32_t code = collectUseDatabase(pName, pCxt->pDbs);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = collectUseTable(pName, pCxt->pTables);
+  }
   if (TSDB_CODE_SUCCESS == code) {
     code = catalogGetTableMeta(pParCxt->pCatalog, pParCxt->pTransporter, &pParCxt->mgmtEpSet, pName, pMeta);
   }
@@ -117,7 +126,10 @@ static int32_t getTableMeta(STranslateContext* pCxt, const char* pDbName, const
 
 static int32_t getTableDistVgInfo(STranslateContext* pCxt, const SName* pName, SArray** pVgInfo) {
   SParseContext* pParCxt = pCxt->pParseCxt;
-  int32_t code = collectUseTable(pName, pCxt->pTables);
+  int32_t code = collectUseDatabase(pName, pCxt->pDbs);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = collectUseTable(pName, pCxt->pTables);
+  }
   if (TSDB_CODE_SUCCESS == code) {
     code = catalogGetTableDistVgInfo(pParCxt->pCatalog, pParCxt->pTransporter, &pParCxt->mgmtEpSet, pName, pVgInfo);
   }
@@ -131,7 +143,7 @@ static int32_t getDBVgInfoImpl(STranslateContext* pCxt, const SName* pName, SArr
   SParseContext* pParCxt = pCxt->pParseCxt;
   char fullDbName[TSDB_DB_FNAME_LEN];
   tNameGetFullDbName(pName, fullDbName);
-  int32_t code = collectUseDatabase(fullDbName, pCxt->pDbs);
+  int32_t code = collectUseDatabaseImpl(fullDbName, pCxt->pDbs);
   if (TSDB_CODE_SUCCESS == code) {
     code = catalogGetDBVgInfo(pParCxt->pCatalog, pParCxt->pTransporter, &pParCxt->mgmtEpSet, fullDbName, pVgInfo);
   }
@@ -151,7 +163,10 @@ static int32_t getDBVgInfo(STranslateContext* pCxt, const char* pDbName, SArray*
 
 static int32_t getTableHashVgroupImpl(STranslateContext* pCxt, const SName* pName, SVgroupInfo* pInfo) {
   SParseContext* pParCxt = pCxt->pParseCxt;
-  int32_t code = collectUseTable(pName, pCxt->pTables);
+  int32_t code = collectUseDatabase(pName, pCxt->pDbs);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = collectUseTable(pName, pCxt->pTables);
+  }
   if (TSDB_CODE_SUCCESS == code) {
     code = catalogGetTableHashVgroup(pParCxt->pCatalog, pParCxt->pTransporter, &pParCxt->mgmtEpSet, pName, pInfo);
   }
@@ -170,7 +185,7 @@ static int32_t getTableHashVgroup(STranslateContext* pCxt, const char* pDbName,
 
 static int32_t getDBVgVersion(STranslateContext* pCxt, const char* pDbFName, int32_t* pVersion, int64_t* pDbId, int32_t* pTableNum) {
   SParseContext* pParCxt = pCxt->pParseCxt;
-  int32_t code = collectUseDatabase(pDbFName, pCxt->pDbs);
+  int32_t code = collectUseDatabaseImpl(pDbFName, pCxt->pDbs);
   if (TSDB_CODE_SUCCESS == code) {
     code = catalogGetDBVgVersion(pParCxt->pCatalog, pDbFName, pVersion, pDbId, pTableNum);
   }
@@ -388,7 +403,7 @@ static EDealRes translateValue(STranslateContext* pCxt, SValueNode* pVal) {
           return generateDealNodeErrMsg(pCxt, TSDB_CODE_OUT_OF_MEMORY);
         }
         varDataSetLen(pVal->datum.p, pVal->node.resType.bytes);
-        strcpy(varDataVal(pVal->datum.p), pVal->literal);
+        strncpy(varDataVal(pVal->datum.p), pVal->literal, pVal->node.resType.bytes);
         break;
       }
       case TSDB_DATA_TYPE_TIMESTAMP: {
@@ -599,9 +614,9 @@ static int32_t toVgroupsInfo(SArray* pVgs, SVgroupsInfo** pVgsInfo) {
 
 static int32_t setSysTableVgroupList(STranslateContext* pCxt, SName* pName, SRealTableNode* pRealTable) {
   // todo release
-  // if (0 != strcmp(pRealTable->table.tableName, TSDB_INS_TABLE_USER_TABLES)) {
-  //   return TSDB_CODE_SUCCESS;
-  // }
+  if (0 != strcmp(pRealTable->table.tableName, TSDB_INS_TABLE_USER_TABLES)) {
+    return TSDB_CODE_SUCCESS;
+  }
 
   int32_t code = TSDB_CODE_SUCCESS;
   SArray* vgroupList = NULL;
@@ -613,9 +628,9 @@ static int32_t setSysTableVgroupList(STranslateContext* pCxt, SName* pName, SRea
 
   if (TSDB_CODE_SUCCESS == code) {
     // todo remove
-    if (NULL != vgroupList && taosArrayGetSize(vgroupList) > 0 && 0 != strcmp(pRealTable->table.tableName, TSDB_INS_TABLE_USER_TABLES)) {
-      taosArrayPopTailBatch(vgroupList, taosArrayGetSize(vgroupList) - 1);
-    }
+    //if (NULL != vgroupList && taosArrayGetSize(vgroupList) > 0 && 0 != strcmp(pRealTable->table.tableName, TSDB_INS_TABLE_USER_TABLES)) {
+    //  taosArrayPopTailBatch(vgroupList, taosArrayGetSize(vgroupList) - 1);
+    //}
 
     code = toVgroupsInfo(vgroupList, &pRealTable->pVgroupList);
   }
@@ -1947,6 +1962,7 @@ static int32_t rewriteShow(STranslateContext* pCxt, SQuery* pQuery) {
     code = createShowCondition((SShowStmt*)pQuery->pRoot, pStmt);
   }
   if (TSDB_CODE_SUCCESS == code) {
+    pQuery->showRewrite = true;
     nodesDestroyNode(pQuery->pRoot);
     pQuery->pRoot = (SNode*)pStmt;
   }
diff --git a/source/libs/planner/src/planLogicCreater.c b/source/libs/planner/src/planLogicCreater.c
index 84fa52a070..6ea476a334 100644
--- a/source/libs/planner/src/planLogicCreater.c
+++ b/source/libs/planner/src/planLogicCreater.c
@@ -161,6 +161,7 @@ static int32_t createScanLogicNode(SLogicPlanContext* pCxt, SSelectStmt* pSelect
   pScan->tableName.acctId = pCxt->pPlanCxt->acctId;
   strcpy(pScan->tableName.dbname, pRealTable->table.dbName);
   strcpy(pScan->tableName.tname, pRealTable->table.tableName);
+  pScan->showRewrite = pCxt->pPlanCxt->showRewrite;
 
   // set columns to scan
   SNodeList* pCols = NULL;
diff --git a/source/libs/planner/src/planPhysiCreater.c b/source/libs/planner/src/planPhysiCreater.c
index fb9a2fc532..d8d090d280 100644
--- a/source/libs/planner/src/planPhysiCreater.c
+++ b/source/libs/planner/src/planPhysiCreater.c
@@ -331,15 +331,14 @@ static int32_t createSystemTableScanPhysiNode(SPhysiPlanContext* pCxt, SSubplan*
     return TSDB_CODE_OUT_OF_MEMORY;
   }
 
+  pScan->showRewrite = pScanLogicNode->showRewrite;
+  pScan->accountId = pCxt->pPlanCxt->acctId;
   if (0 == strcmp(pScanLogicNode->tableName.tname, TSDB_INS_TABLE_USER_TABLES)) {
     vgroupInfoToNodeAddr(pScanLogicNode->pVgroupList->vgroups, &pSubplan->execNode);
     taosArrayPush(pCxt->pExecNodeList, &pSubplan->execNode);
   } else {
-    for (int32_t i = 0; i < pScanLogicNode->pVgroupList->numOfVgroups; ++i) {
-      SQueryNodeAddr addr;
-      vgroupInfoToNodeAddr(pScanLogicNode->pVgroupList->vgroups + i, &addr);
-      taosArrayPush(pCxt->pExecNodeList, &addr);
-    }
+    SQueryNodeAddr addr = { .nodeId = MND_VGID, .epSet = pCxt->pPlanCxt->mgmtEpSet };
+    taosArrayPush(pCxt->pExecNodeList, &addr);
   }
   pScan->mgmtEpSet = pCxt->pPlanCxt->mgmtEpSet;
   tNameGetFullDbName(&pScanLogicNode->tableName, pSubplan->dbFName);
diff --git a/source/libs/qcom/src/queryUtil.c b/source/libs/qcom/src/queryUtil.c
index 79a59a5ecb..0cf46edf11 100644
--- a/source/libs/qcom/src/queryUtil.c
+++ b/source/libs/qcom/src/queryUtil.c
@@ -140,7 +140,7 @@ int32_t taosAsyncExec(__async_exec_fn_t execFn, void* execParam, int32_t* code)
   return 0;
 }
 
-int32_t asyncSendMsgToServer(void* pTransporter, SEpSet* epSet, int64_t* pTransporterId, const SMsgSendInfo* pInfo) {
+int32_t asyncSendMsgToServerExt(void* pTransporter, SEpSet* epSet, int64_t* pTransporterId, const SMsgSendInfo* pInfo, bool persistHandle, void *rpcCtx) {
   char* pMsg = rpcMallocCont(pInfo->msgInfo.len);
   if (NULL == pMsg) {
     qError("0x%" PRIx64 " msg:%s malloc failed", pInfo->requestId, TMSG_INFO(pInfo->msgType));
@@ -154,6 +154,7 @@ int32_t asyncSendMsgToServer(void* pTransporter, SEpSet* epSet, int64_t* pTransp
                     .contLen = pInfo->msgInfo.len,
                     .ahandle = (void*)pInfo,
                     .handle = pInfo->msgInfo.handle,
+                    .persistHandle = persistHandle,
                     .code = 0};
   if (pInfo->msgType == TDMT_VND_QUERY || pInfo->msgType == TDMT_VND_FETCH ||
       pInfo->msgType == TDMT_VND_QUERY_CONTINUE) {
@@ -162,10 +163,14 @@ int32_t asyncSendMsgToServer(void* pTransporter, SEpSet* epSet, int64_t* pTransp
 
   assert(pInfo->fp != NULL);
 
-  rpcSendRequest(pTransporter, epSet, &rpcMsg, pTransporterId);
+  rpcSendRequestWithCtx(pTransporter, epSet, &rpcMsg, pTransporterId, rpcCtx);
   return TSDB_CODE_SUCCESS;
 }
 
+int32_t asyncSendMsgToServer(void* pTransporter, SEpSet* epSet, int64_t* pTransporterId, const SMsgSendInfo* pInfo) {
+  return asyncSendMsgToServerExt(pTransporter, epSet, pTransporterId, pInfo, false, NULL);
+}
+
 char *jobTaskStatusStr(int32_t status) {
   switch (status) {
     case JOB_TASK_STATUS_NULL:
diff --git a/source/libs/qworker/inc/qworkerInt.h b/source/libs/qworker/inc/qworkerInt.h
index e768aa2de0..573eaed2e6 100644
--- a/source/libs/qworker/inc/qworkerInt.h
+++ b/source/libs/qworker/inc/qworkerInt.h
@@ -69,18 +69,24 @@ enum {
 typedef struct SQWDebug {
   bool lockEnable;
   bool statusEnable;
+  bool dumpEnable;
 } SQWDebug;
 
+typedef struct SQWConnInfo {
+  void *handle;
+  void *ahandle;
+} SQWConnInfo;
+
 typedef struct SQWMsg {
-  void   *node;
-  char   *msg;
-  int32_t msgLen;
-  void   *connection;
+  void        *node;
+  char        *msg;
+  int32_t      msgLen;
+  SQWConnInfo  connInfo;
 } SQWMsg;
 
 typedef struct SQWHbInfo {
   SSchedulerHbRsp  rsp;
-  void            *connection;
+  SQWConnInfo      connInfo;
 } SQWHbInfo;
 
 typedef struct SQWPhaseInput {
@@ -101,10 +107,6 @@ typedef struct SQWTaskCtx {
   SRWLatch        lock;
   int8_t          phase;
   int8_t          taskType;
-
-  void           *readyConnection;
-  void           *dropConnection;
-  void           *cancelConnection;
   
   bool            emptyRes;
   bool            queryFetched;
@@ -113,6 +115,7 @@ typedef struct SQWTaskCtx {
   bool            queryInQueue;
   int32_t         rspCode; 
 
+  SQWConnInfo     connInfo;
   int8_t          events[QW_EVENT_MAX];
   
   qTaskInfo_t     taskHandle;
@@ -120,11 +123,12 @@ typedef struct SQWTaskCtx {
 } SQWTaskCtx;
 
 typedef struct SQWSchStatus {
-  int32_t   lastAccessTs; // timestamp in second
-  uint64_t  hbSeqId;
-  void     *hbConnection;
-  SRWLatch  tasksLock;
-  SHashObj *tasksHash;   // key:queryId+taskId, value: SQWTaskStatus
+  int32_t        lastAccessTs; // timestamp in second
+  SRWLatch       hbConnLock;
+  SQWConnInfo    hbConnInfo;
+  SQueryNodeEpId hbEpId;  
+  SRWLatch       tasksLock;
+  SHashObj      *tasksHash;   // key:queryId+taskId, value: SQWTaskStatus
 } SQWSchStatus;
 
 // Qnode/Vnode level task management
@@ -172,12 +176,16 @@ typedef struct SQWorkerMgmt {
 #define QW_ELOG(param, ...) qError("QW:%p " param, mgmt, __VA_ARGS__)
 #define QW_DLOG(param, ...) qDebug("QW:%p " param, mgmt, __VA_ARGS__)
 
+#define QW_DUMP(param, ...) do { if (gQWDebug.dumpEnable) { qDebug("QW:%p " param, mgmt, __VA_ARGS__); } } while (0)
+
+
 #define QW_SCH_ELOG(param, ...) qError("QW:%p SID:%"PRIx64" " param, mgmt, sId, __VA_ARGS__)
 #define QW_SCH_DLOG(param, ...) qDebug("QW:%p SID:%"PRIx64" " param, mgmt, sId, __VA_ARGS__)
 
 #define QW_TASK_ELOG(param, ...) qError("QW:%p QID:0x%"PRIx64",TID:0x%"PRIx64" " param, mgmt, qId, tId, __VA_ARGS__)
 #define QW_TASK_WLOG(param, ...) qWarn("QW:%p QID:0x%"PRIx64",TID:0x%"PRIx64" " param, mgmt, qId, tId, __VA_ARGS__)
 #define QW_TASK_DLOG(param, ...) qDebug("QW:%p QID:0x%"PRIx64",TID:0x%"PRIx64" " param, mgmt, qId, tId, __VA_ARGS__)
+#define QW_TASK_DLOGL(param, ...) qDebugL("QW:%p QID:0x%"PRIx64",TID:0x%"PRIx64" " param, mgmt, qId, tId, __VA_ARGS__)
 
 #define QW_TASK_ELOG_E(param) qError("QW:%p QID:0x%"PRIx64",TID:0x%"PRIx64" " param, mgmt, qId, tId)
 #define QW_TASK_WLOG_E(param) qWarn("QW:%p QID:0x%"PRIx64",TID:0x%"PRIx64" " param, mgmt, qId, tId)
@@ -223,8 +231,6 @@ typedef struct SQWorkerMgmt {
   }                                                       \
 } while (0)
 
-int32_t qwBuildAndSendCancelRsp(SRpcMsg *pMsg, int32_t code);
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/libs/qworker/inc/qworkerMsg.h b/source/libs/qworker/inc/qworkerMsg.h
index ecb5dbd654..be1d47a189 100644
--- a/source/libs/qworker/inc/qworkerMsg.h
+++ b/source/libs/qworker/inc/qworkerMsg.h
@@ -30,17 +30,18 @@ int32_t qwProcessFetch(QW_FPARAMS_DEF, SQWMsg *qwMsg);
 int32_t qwProcessDrop(QW_FPARAMS_DEF, SQWMsg *qwMsg);
 int32_t qwProcessHb(SQWorkerMgmt *mgmt, SQWMsg *qwMsg, SSchedulerHbReq *req);
 
-int32_t qwBuildAndSendDropRsp(void *connection, int32_t code);
-int32_t qwBuildAndSendCancelRsp(SRpcMsg *pMsg, int32_t code);
-int32_t qwBuildAndSendFetchRsp(void *connection, SRetrieveTableRsp *pRsp, int32_t dataLength, int32_t code);
+int32_t qwBuildAndSendDropRsp(SQWConnInfo *pConn, int32_t code);
+int32_t qwBuildAndSendCancelRsp(SQWConnInfo *pConn, int32_t code);
+int32_t qwBuildAndSendFetchRsp(SQWConnInfo *pConn, SRetrieveTableRsp *pRsp, int32_t dataLength, int32_t code);
 void qwBuildFetchRsp(void *msg, SOutputData *input, int32_t len, bool qComplete);
-int32_t qwBuildAndSendCQueryMsg(QW_FPARAMS_DEF, void *connection);
-int32_t qwBuildAndSendReadyRsp(void *connection, int32_t code);
-int32_t qwBuildAndSendQueryRsp(void *connection, int32_t code);
+int32_t qwBuildAndSendCQueryMsg(QW_FPARAMS_DEF, SQWConnInfo *pConn);
+int32_t qwBuildAndSendReadyRsp(SQWConnInfo *pConn, int32_t code);
+int32_t qwBuildAndSendQueryRsp(SQWConnInfo *pConn, int32_t code);
 void qwFreeFetchRsp(void *msg);
 int32_t qwMallocFetchRsp(int32_t length, SRetrieveTableRsp **rsp);
 int32_t qwGetSchTasksStatus(SQWorkerMgmt *mgmt, uint64_t sId, SSchedulerStatusRsp **rsp);
-int32_t qwBuildAndSendHbRsp(SRpcMsg *pMsg, SSchedulerHbRsp *rsp, int32_t code);
+int32_t qwBuildAndSendHbRsp(SQWConnInfo *pConn, SSchedulerHbRsp *rsp, int32_t code);
+int32_t qwRegisterBrokenLinkArg(QW_FPARAMS_DEF, SQWConnInfo *pConn);
 
 
 
diff --git a/source/libs/qworker/src/qworker.c b/source/libs/qworker/src/qworker.c
index 641fe82a85..70ca0f736b 100644
--- a/source/libs/qworker/src/qworker.c
+++ b/source/libs/qworker/src/qworker.c
@@ -9,7 +9,7 @@
 #include "tname.h"
 #include "dataSinkMgt.h"
 
-SQWDebug gQWDebug = {.statusEnable = true};
+SQWDebug gQWDebug = {.statusEnable = true, .dumpEnable = true};
 
 int32_t qwDbgValidateStatus(QW_FPARAMS_DEF, int8_t oriStatus, int8_t newStatus, bool *ignore) {
   if (!gQWDebug.statusEnable) {
@@ -103,6 +103,36 @@ _return:
   QW_RET(code);
 }
 
+void qwDbgDumpSchInfo(SQWSchStatus *sch, int32_t i) {
+
+}
+
+void qwDbgDumpMgmtInfo(SQWorkerMgmt *mgmt) {
+  if (!gQWDebug.dumpEnable) {
+    return;
+  }
+
+  QW_LOCK(QW_READ, &mgmt->schLock);
+  
+  QW_DUMP("total remain schduler num:%d", taosHashGetSize(mgmt->schHash));
+
+  void *key = NULL;
+  size_t keyLen = 0;
+  int32_t i = 0;
+  SQWSchStatus *sch = NULL;
+
+  void *pIter = taosHashIterate(mgmt->schHash, NULL);
+  while (pIter) {
+    sch = (SQWSchStatus *)pIter;
+    qwDbgDumpSchInfo(sch, i);
+    ++i;
+    pIter = taosHashIterate(mgmt->schHash, pIter);
+  }
+
+  QW_UNLOCK(QW_READ, &mgmt->schLock);
+
+  QW_DUMP("total remain ctx num:%d", taosHashGetSize(mgmt->ctxHash));
+}
 
 char *qwPhaseStr(int32_t phase) {
   switch (phase) {
@@ -166,7 +196,7 @@ int32_t qwSetTaskStatus(QW_FPARAMS_DEF, SQWTaskStatus *task, int8_t status) {
 }
 
 
-int32_t qwAddSchedulerImpl(SQWorkerMgmt *mgmt, uint64_t sId, int32_t rwType, SQWSchStatus **sch) {
+int32_t qwAddSchedulerImpl(SQWorkerMgmt *mgmt, uint64_t sId, int32_t rwType) {
   SQWSchStatus newSch = {0};
   newSch.tasksHash = taosHashInit(mgmt->cfg.maxSchTaskNum, taosGetDefaultHashFunction(TSDB_DATA_TYPE_BINARY), false, HASH_NO_LOCK);
   if (NULL == newSch.tasksHash) {
@@ -200,7 +230,7 @@ int32_t qwAcquireSchedulerImpl(SQWorkerMgmt *mgmt, uint64_t sId, int32_t rwType,
       QW_UNLOCK(rwType, &mgmt->schLock);
       
       if (QW_NOT_EXIST_ADD == nOpt) {
-        QW_ERR_RET(qwAddSchedulerImpl(mgmt, sId, rwType, sch));
+        QW_ERR_RET(qwAddSchedulerImpl(mgmt, sId, rwType));
 
         nOpt = QW_NOT_EXIST_RET_ERR;
         
@@ -402,6 +432,9 @@ int32_t qwKillTaskHandle(QW_FPARAMS_DEF, SQWTaskCtx *ctx) {
 
 
 void qwFreeTask(QW_FPARAMS_DEF, SQWTaskCtx *ctx) {
+  rpcReleaseHandle(ctx->connInfo.handle, TAOS_CONN_SERVER);
+  ctx->connInfo.handle = NULL;
+
   qwFreeTaskHandle(QW_FPARAMS(), &ctx->taskHandle);
   
   if (ctx->sinkHandle) {
@@ -516,7 +549,7 @@ int32_t qwExecTask(QW_FPARAMS_DEF, SQWTaskCtx *ctx, bool *queryEnd) {
  
   while (true) {
     QW_TASK_DLOG("start to execTask, loopIdx:%d", i++);
-    
+
     code = qExecTask(*taskHandle, &pRes, &useconds);
     if (code) {
       QW_TASK_ELOG("qExecTask failed, code:%x - %s", code, tstrerror(code));
@@ -577,6 +610,9 @@ int32_t qwExecTask(QW_FPARAMS_DEF, SQWTaskCtx *ctx, bool *queryEnd) {
 int32_t qwGenerateSchHbRsp(SQWorkerMgmt *mgmt, SQWSchStatus *sch, SQWHbInfo *hbInfo) {
   int32_t taskNum = 0;
 
+  hbInfo->connInfo = sch->hbConnInfo;
+  hbInfo->rsp.epId = sch->hbEpId;
+
   QW_LOCK(QW_READ, &sch->tasksLock);
   
   taskNum = taosHashGetSize(sch->tasksHash);
@@ -588,9 +624,6 @@ int32_t qwGenerateSchHbRsp(SQWorkerMgmt *mgmt, SQWSchStatus *sch, SQWHbInfo *hbI
     return TSDB_CODE_QRY_OUT_OF_MEMORY;
   }
 
-  hbInfo->connection = sch->hbConnection;
-  hbInfo->rsp.seqId = -1;
-
   void *key = NULL;
   size_t keyLen = 0;
   int32_t i = 0;
@@ -694,8 +727,8 @@ int32_t qwGetResFromSink(QW_FPARAMS_DEF, SQWTaskCtx *ctx, int32_t *dataLen, void
 int32_t qwHandlePrePhaseEvents(QW_FPARAMS_DEF, int8_t phase, SQWPhaseInput *input, SQWPhaseOutput *output) {
   int32_t code = 0;
   SQWTaskCtx *ctx = NULL;
-  void *dropConnection = NULL;
-  void *cancelConnection = NULL;
+  SQWConnInfo *dropConnection = NULL;
+  SQWConnInfo *cancelConnection = NULL;
 
   QW_TASK_DLOG("start to handle event at phase %s", qwPhaseStr(phase));
 
@@ -727,9 +760,13 @@ int32_t qwHandlePrePhaseEvents(QW_FPARAMS_DEF, int8_t phase, SQWPhaseInput *inpu
       }
 
       if (QW_IS_EVENT_RECEIVED(ctx, QW_EVENT_DROP)) {
+        dropConnection = &ctx->connInfo;
         QW_ERR_JRET(qwDropTask(QW_FPARAMS()));
+        dropConnection = NULL;
+        
+        qwBuildAndSendDropRsp(&ctx->connInfo, code);    
+        QW_TASK_DLOG("drop rsp send, handle:%p, code:%x - %s", ctx->connInfo.handle, code, tstrerror(code));
 
-        dropConnection = ctx->dropConnection;
         QW_ERR_JRET(TSDB_CODE_QRY_TASK_DROPPED);
         break;
       }
@@ -761,9 +798,13 @@ int32_t qwHandlePrePhaseEvents(QW_FPARAMS_DEF, int8_t phase, SQWPhaseInput *inpu
       }
 
       if (QW_IS_EVENT_RECEIVED(ctx, QW_EVENT_DROP)) {
+        dropConnection = &ctx->connInfo;
         QW_ERR_JRET(qwDropTask(QW_FPARAMS()));
+        dropConnection = NULL;
 
-        dropConnection = ctx->dropConnection;
+        qwBuildAndSendDropRsp(&ctx->connInfo, code);
+        QW_TASK_DLOG("drop rsp send, handle:%p, code:%x - %s", ctx->connInfo.handle, code, tstrerror(code));
+        
         QW_ERR_JRET(TSDB_CODE_QRY_TASK_DROPPED);
       }
 
@@ -789,13 +830,13 @@ _return:
   }
 
   if (dropConnection) {
-    qwBuildAndSendDropRsp(dropConnection, code);
-    QW_TASK_DLOG("drop msg rsped, code:%x - %s", code, tstrerror(code));
+    qwBuildAndSendDropRsp(dropConnection, code);    
+    QW_TASK_DLOG("drop rsp send, handle:%p, code:%x - %s", dropConnection->handle, code, tstrerror(code));
   }
 
   if (cancelConnection) {
-    qwBuildAndSendCancelRsp(cancelConnection, code);
-    QW_TASK_DLOG("cancel msg rsped, code:%x - %s", code, tstrerror(code));
+    qwBuildAndSendCancelRsp(cancelConnection, code);    
+    QW_TASK_DLOG("cancel rsp send, handle:%p, code:%x - %s", cancelConnection->handle, code, tstrerror(code));
   }
 
   QW_TASK_DLOG("end to handle event at phase %s, code:%x - %s", qwPhaseStr(phase), code, tstrerror(code));
@@ -807,9 +848,8 @@ _return:
 int32_t qwHandlePostPhaseEvents(QW_FPARAMS_DEF, int8_t phase, SQWPhaseInput *input, SQWPhaseOutput *output) {
   int32_t code = 0;
   SQWTaskCtx *ctx = NULL;
-  void *readyConnection = NULL;
-  void *dropConnection = NULL;
-  void *cancelConnection = NULL;
+  SQWConnInfo connInfo = {0};
+  SQWConnInfo *readyConnection = NULL;
 
   QW_TASK_DLOG("start to handle event at phase %s", qwPhaseStr(phase));
   
@@ -826,11 +866,18 @@ int32_t qwHandlePostPhaseEvents(QW_FPARAMS_DEF, int8_t phase, SQWPhaseInput *inp
     if (NULL == ctx->taskHandle && NULL == ctx->sinkHandle) {
       ctx->emptyRes = true;
     }
-    
+
+#if 0    
     if (QW_IS_EVENT_RECEIVED(ctx, QW_EVENT_READY)) {
-      readyConnection = ctx->readyConnection;
+      readyConnection = &ctx->connInfo;
       QW_SET_EVENT_PROCESSED(ctx, QW_EVENT_READY);
     }
+#else
+    connInfo.handle = ctx->connInfo.handle;
+    readyConnection = &connInfo;
+    
+    QW_SET_EVENT_PROCESSED(ctx, QW_EVENT_READY);
+#endif
   }
 
   if (QW_IS_EVENT_RECEIVED(ctx, QW_EVENT_DROP)) {
@@ -838,10 +885,11 @@ int32_t qwHandlePostPhaseEvents(QW_FPARAMS_DEF, int8_t phase, SQWPhaseInput *inp
       QW_TASK_WLOG("drop received at wrong phase %s", qwPhaseStr(phase));
       QW_ERR_JRET(TSDB_CODE_QRY_APP_ERROR);
     }
+
+    qwBuildAndSendDropRsp(&ctx->connInfo, code);    
+    QW_TASK_DLOG("drop rsp send, handle:%p, code:%x - %s", ctx->connInfo.handle, code, tstrerror(code));
     
     QW_ERR_JRET(qwDropTask(QW_FPARAMS()));
-
-    dropConnection = ctx->dropConnection;
     QW_ERR_JRET(TSDB_CODE_QRY_TASK_DROPPED);
   }
 
@@ -870,18 +918,8 @@ _return:
   }
 
   if (readyConnection) {
-    qwBuildAndSendReadyRsp(readyConnection, code);
-    QW_TASK_DLOG("ready msg rsped, code:%x - %s", code, tstrerror(code));
-  }
-
-  if (dropConnection) {
-    qwBuildAndSendDropRsp(dropConnection, code);
-    QW_TASK_DLOG("drop msg rsped, code:%x - %s", code, tstrerror(code));
-  }
-
-  if (cancelConnection) {
-    qwBuildAndSendCancelRsp(cancelConnection, code);
-    QW_TASK_DLOG("cancel msg rsped, code:%x - %s", code, tstrerror(code));
+    qwBuildAndSendReadyRsp(readyConnection, code);    
+    QW_TASK_DLOG("ready msg rsped, handle:%p, code:%x - %s", readyConnection->handle, code, tstrerror(code));
   }
 
   if (code) {
@@ -893,23 +931,26 @@ _return:
   QW_RET(code);
 }
 
-
 int32_t qwProcessQuery(QW_FPARAMS_DEF, SQWMsg *qwMsg, int8_t taskType) {
   int32_t code = 0;
   bool queryRsped = false;
-  bool needStop = false;
   struct SSubplan *plan = NULL;
   SQWPhaseInput input = {0};
   qTaskInfo_t pTaskInfo = NULL;
   DataSinkHandle sinkHandle = NULL;
   SQWTaskCtx *ctx = NULL;
 
+  QW_ERR_JRET(qwRegisterBrokenLinkArg(QW_FPARAMS(), &qwMsg->connInfo));
+
   QW_ERR_JRET(qwHandlePrePhaseEvents(QW_FPARAMS(), QW_PHASE_PRE_QUERY, &input, NULL));
 
   QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), &ctx));
   
   atomic_store_8(&ctx->taskType, taskType);
-  
+  atomic_store_ptr(&ctx->connInfo.handle, qwMsg->connInfo.handle);
+  atomic_store_ptr(&ctx->connInfo.ahandle, qwMsg->connInfo.ahandle);
+
+  QW_TASK_DLOGL("subplan json string, len:%d, %s", qwMsg->msgLen, qwMsg->msg);
   code = qStringToSubplan(qwMsg->msg, &plan);
   if (TSDB_CODE_SUCCESS != code) {
     QW_TASK_ELOG("task string to subplan failed, code:%x - %s", code, tstrerror(code));
@@ -927,8 +968,8 @@ int32_t qwProcessQuery(QW_FPARAMS_DEF, SQWMsg *qwMsg, int8_t taskType) {
     QW_ERR_JRET(TSDB_CODE_QRY_APP_ERROR);
   }
 
-  QW_ERR_JRET(qwBuildAndSendQueryRsp(qwMsg->connection, code));
-  QW_TASK_DLOG("query msg rsped, code:%x - %s", code, tstrerror(code));
+  QW_ERR_JRET(qwBuildAndSendQueryRsp(&qwMsg->connInfo, code));
+  QW_TASK_DLOG("query msg rsped, handle:%p, code:%x - %s", qwMsg->connInfo.handle, code, tstrerror(code));
 
   queryRsped = true;
 
@@ -945,11 +986,11 @@ _return:
   code = qwHandlePostPhaseEvents(QW_FPARAMS(), QW_PHASE_POST_QUERY, &input, NULL);
   
   if (!queryRsped) {
-    qwBuildAndSendQueryRsp(qwMsg->connection, code);
-    QW_TASK_DLOG("query msg rsped, code:%x - %s", code, tstrerror(code));
+    qwBuildAndSendQueryRsp(&qwMsg->connInfo, code);
+    QW_TASK_DLOG("query msg rsped, handle:%p, code:%x - %s", qwMsg->connInfo.handle, code, tstrerror(code));
   }
 
-  QW_RET(code);
+  QW_RET(TSDB_CODE_SUCCESS);
 }
 
 int32_t qwProcessReady(QW_FPARAMS_DEF, SQWMsg *qwMsg) {
@@ -968,8 +1009,9 @@ int32_t qwProcessReady(QW_FPARAMS_DEF, SQWMsg *qwMsg) {
   }
   
   if (ctx->phase == QW_PHASE_PRE_QUERY) {
+    ctx->connInfo.handle == qwMsg->connInfo.handle;
+    ctx->connInfo.ahandle = qwMsg->connInfo.ahandle;
     QW_SET_EVENT_RECEIVED(ctx, QW_EVENT_READY);
-    ctx->readyConnection = qwMsg->connection;
     needRsp = false;
     QW_TASK_DLOG_E("ready msg will not rsp now");
     goto _return;
@@ -1007,11 +1049,11 @@ _return:
   }
 
   if (needRsp) {
-    qwBuildAndSendReadyRsp(qwMsg->connection, code);
-    QW_TASK_DLOG("ready msg rsped, code:%x - %s", code, tstrerror(code));
+    qwBuildAndSendReadyRsp(&qwMsg->connInfo, code);
+    QW_TASK_DLOG("ready msg rsped, handle:%p, code:%x - %s", qwMsg->connInfo.handle, code, tstrerror(code));
   }
 
-  QW_RET(code);
+  QW_RET(TSDB_CODE_SUCCESS);
 }
 
 
@@ -1048,10 +1090,11 @@ int32_t qwProcessCQuery(QW_FPARAMS_DEF, SQWMsg *qwMsg) {
         qwBuildFetchRsp(rsp, &sOutput, dataLen, qComplete);
         atomic_store_8((int8_t*)&ctx->queryEnd, qComplete);
 
+        qwMsg->connInfo = ctx->connInfo;
         QW_SET_EVENT_PROCESSED(ctx, QW_EVENT_FETCH);            
         
-        qwBuildAndSendFetchRsp(qwMsg->connection, rsp, dataLen, code);                
-        QW_TASK_DLOG("fetch msg rsped, code:%x, dataLen:%d", code, dataLen);
+        qwBuildAndSendFetchRsp(&qwMsg->connInfo, rsp, dataLen, code);                
+        QW_TASK_DLOG("fetch rsp send, handle:%p, code:%x - %s, dataLen:%d", qwMsg->connInfo.handle, code, tstrerror(code), dataLen);
       } else {
         atomic_store_8((int8_t*)&ctx->queryContinue, 1);
       }
@@ -1067,8 +1110,10 @@ _return:
       QW_SET_EVENT_PROCESSED(ctx, QW_EVENT_FETCH);    
       qwFreeFetchRsp(rsp);
       rsp = NULL;
-      qwBuildAndSendFetchRsp(qwMsg->connection, rsp, 0, code);
-      QW_TASK_DLOG("fetch msg rsped, code:%x - %s", code, tstrerror(code));
+      
+      qwMsg->connInfo = ctx->connInfo;
+      qwBuildAndSendFetchRsp(&qwMsg->connInfo, rsp, 0, code);
+      QW_TASK_DLOG("fetch rsp send, handle:%p, code:%x - %s, dataLen:%d", qwMsg->connInfo.handle, code, tstrerror(code), 0);
     }
 
     QW_LOCK(QW_WRITE, &ctx->lock);
@@ -1082,7 +1127,9 @@ _return:
   } while (true);
 
   input.code = code;
-  QW_RET(qwHandlePostPhaseEvents(QW_FPARAMS(), QW_PHASE_POST_CQUERY, &input, NULL));
+  qwHandlePostPhaseEvents(QW_FPARAMS(), QW_PHASE_POST_CQUERY, &input, NULL);    
+
+  QW_RET(TSDB_CODE_SUCCESS);  
 }
 
 
@@ -1097,11 +1144,14 @@ int32_t qwProcessFetch(QW_FPARAMS_DEF, SQWMsg *qwMsg) {
   QW_ERR_JRET(qwHandlePrePhaseEvents(QW_FPARAMS(), QW_PHASE_PRE_FETCH, &input, NULL));
 
   QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), &ctx));
- 
+  
   SOutputData sOutput = {0};
   QW_ERR_JRET(qwGetResFromSink(QW_FPARAMS(), ctx, &dataLen, &rsp, &sOutput));
 
   if (NULL == rsp) {
+    atomic_store_ptr(&ctx->connInfo.handle, qwMsg->connInfo.handle);
+    atomic_store_ptr(&ctx->connInfo.ahandle, qwMsg->connInfo.ahandle);
+    
     QW_SET_EVENT_RECEIVED(ctx, QW_EVENT_FETCH);
   } else {
     bool qComplete = (DS_BUF_EMPTY == sOutput.bufStatus && sOutput.queryEnd);
@@ -1123,7 +1173,7 @@ int32_t qwProcessFetch(QW_FPARAMS_DEF, SQWMsg *qwMsg) {
 
       atomic_store_8((int8_t*)&ctx->queryInQueue, 1);
       
-      QW_ERR_JRET(qwBuildAndSendCQueryMsg(QW_FPARAMS(), qwMsg->connection));
+      QW_ERR_JRET(qwBuildAndSendCQueryMsg(QW_FPARAMS(), &qwMsg->connInfo));
     }
   }
   
@@ -1143,17 +1193,17 @@ _return:
   }
 
   if (code || rsp) {
-    qwBuildAndSendFetchRsp(qwMsg->connection, rsp, dataLen, code);
-    QW_TASK_DLOG("fetch msg rsped, code:%x, dataLen:%d", code, dataLen);
+    qwBuildAndSendFetchRsp(&qwMsg->connInfo, rsp, dataLen, code);
+    QW_TASK_DLOG("fetch rsp send, handle:%p, code:%x - %s, dataLen:%d", qwMsg->connInfo.handle, code, tstrerror(code), dataLen);
   }
 
-  QW_RET(code);
+  QW_RET(TSDB_CODE_SUCCESS);
 }
 
 
 int32_t qwProcessDrop(QW_FPARAMS_DEF, SQWMsg *qwMsg) {
   int32_t code = 0;
-  bool needRsp = false;
+  bool rsped = false;
   SQWTaskCtx *ctx = NULL;
   bool locked = false;
 
@@ -1174,14 +1224,18 @@ int32_t qwProcessDrop(QW_FPARAMS_DEF, SQWMsg *qwMsg) {
     QW_ERR_JRET(qwKillTaskHandle(QW_FPARAMS(), ctx));
     qwUpdateTaskStatus(QW_FPARAMS(), JOB_TASK_STATUS_DROPPING);
   } else if (ctx->phase > 0) {
+    qwBuildAndSendDropRsp(&qwMsg->connInfo, code);
+    QW_TASK_DLOG("drop rsp send, handle:%p, code:%x - %s", qwMsg->connInfo.handle, code, tstrerror(code));
+  
     QW_ERR_JRET(qwDropTask(QW_FPARAMS()));
-    needRsp = true;
+    rsped = true;
   } else {
     // task not started
   }
 
-  if (!needRsp) {    
-    ctx->dropConnection = qwMsg->connection;
+  if (!rsped) {
+    ctx->connInfo.handle = qwMsg->connInfo.handle;
+    ctx->connInfo.ahandle = qwMsg->connInfo.ahandle;
     
     QW_SET_EVENT_RECEIVED(ctx, QW_EVENT_DROP);
   }
@@ -1204,13 +1258,12 @@ _return:
     qwReleaseTaskCtx(mgmt, ctx);
   }
 
-  if (TSDB_CODE_SUCCESS != code || needRsp) {
-    QW_ERR_RET(qwBuildAndSendDropRsp(qwMsg->connection, code));
-
-    QW_TASK_DLOG("drop msg rsped, code:%x", code);
+  if (TSDB_CODE_SUCCESS != code) {
+    qwBuildAndSendDropRsp(&qwMsg->connInfo, code);
+    QW_TASK_DLOG("drop rsp send, handle:%p, code:%x - %s", qwMsg->connInfo.handle, code, tstrerror(code));
   }
 
-  QW_RET(code);
+  QW_RET(TSDB_CODE_SUCCESS);
 }
 
 int32_t qwProcessHb(SQWorkerMgmt *mgmt, SQWMsg *qwMsg, SSchedulerHbReq *req) {
@@ -1218,38 +1271,46 @@ int32_t qwProcessHb(SQWorkerMgmt *mgmt, SQWMsg *qwMsg, SSchedulerHbReq *req) {
   SSchedulerHbRsp rsp = {0};
   SQWSchStatus *sch = NULL;
   uint64_t seqId = 0;
+  void *origHandle = NULL;
 
   memcpy(&rsp.epId, &req->epId, sizeof(req->epId));
   
   QW_ERR_JRET(qwAcquireAddScheduler(mgmt, req->sId, QW_READ, &sch));
 
-  atomic_store_ptr(&sch->hbConnection, qwMsg->connection);
-  ++sch->hbSeqId;
+  QW_LOCK(QW_WRITE, &sch->hbConnLock);
 
-  rsp.seqId = sch->hbSeqId;
-
-  QW_DLOG("hb connection updated, seqId:%" PRIx64 ", sId:%" PRIx64 ", nodeId:%d, fqdn:%s, port:%d, connection:%p",
-    sch->hbSeqId, req->sId, req->epId.nodeId, req->epId.ep.fqdn, req->epId.ep.port, qwMsg->connection);
+  if (sch->hbConnInfo.handle) {
+    rpcReleaseHandle(sch->hbConnInfo.handle, TAOS_CONN_SERVER);
+  }
+  
+  memcpy(&sch->hbConnInfo, &qwMsg->connInfo, sizeof(qwMsg->connInfo));
+  memcpy(&sch->hbEpId, &req->epId, sizeof(req->epId));
+  
+  QW_UNLOCK(QW_WRITE, &sch->hbConnLock);
+  
+  QW_DLOG("hb connection updated, sId:%" PRIx64 ", nodeId:%d, fqdn:%s, port:%d, handle:%p, ahandle:%p",
+    req->sId, req->epId.nodeId, req->epId.ep.fqdn, req->epId.ep.port, qwMsg->connInfo.handle, qwMsg->connInfo.ahandle);
 
   qwReleaseScheduler(QW_READ, mgmt);
 
 _return:
 
-  qwBuildAndSendHbRsp(qwMsg->connection, &rsp, code);
+  qwBuildAndSendHbRsp(&qwMsg->connInfo, &rsp, code);
+  QW_DLOG("hb rsp send, handle:%p, code:%x - %s", qwMsg->connInfo.handle, code, tstrerror(code));
   
-  QW_RET(code);
+  QW_RET(TSDB_CODE_SUCCESS);
 }
 
 
 void qwProcessHbTimerEvent(void *param, void *tmrId) {
-  return;
-  
   SQWorkerMgmt *mgmt = (SQWorkerMgmt *)param;
   SQWSchStatus *sch = NULL;
   int32_t taskNum = 0;
   SQWHbInfo *rspList = NULL;
   int32_t code = 0;
 
+  qwDbgDumpMgmtInfo(mgmt);
+
   QW_LOCK(QW_READ, &mgmt->schLock);
 
   int32_t schNum = taosHashGetSize(mgmt->schHash);
@@ -1288,8 +1349,8 @@ _return:
   QW_UNLOCK(QW_READ, &mgmt->schLock);
 
   for (int32_t j = 0; j < i; ++j) {
-    QW_DLOG("hb on connection %p, taskNum:%d", rspList[j].connection, (rspList[j].rsp.taskStatus ? (int32_t)taosArrayGetSize(rspList[j].rsp.taskStatus) : 0));
-    qwBuildAndSendHbRsp(rspList[j].connection, &rspList[j].rsp, code);
+    qwBuildAndSendHbRsp(&rspList[j].connInfo, &rspList[j].rsp, code);
+    QW_DLOG("hb rsp send, handle:%p, code:%x - %s, taskNum:%d", rspList[j].connInfo.handle, code, tstrerror(code), (rspList[j].rsp.taskStatus ? (int32_t)taosArrayGetSize(rspList[j].rsp.taskStatus) : 0));    
     tFreeSSchedulerHbRsp(&rspList[j].rsp);
   }
 
diff --git a/source/libs/qworker/src/qworkerMsg.c b/source/libs/qworker/src/qworkerMsg.c
index 56267c462b..dd1f200272 100644
--- a/source/libs/qworker/src/qworkerMsg.c
+++ b/source/libs/qworker/src/qworkerMsg.c
@@ -26,6 +26,8 @@ int32_t qwMallocFetchRsp(int32_t length, SRetrieveTableRsp **rsp) {
   return TSDB_CODE_SUCCESS;
 }
 
+
+
 void qwBuildFetchRsp(void *msg, SOutputData *input, int32_t len, bool qComplete) {
   SRetrieveTableRsp *rsp = (SRetrieveTableRsp *)msg;
   
@@ -44,8 +46,7 @@ void qwFreeFetchRsp(void *msg) {
   }
 }
 
-int32_t qwBuildAndSendQueryRsp(void *connection, int32_t code) {
-  SRpcMsg *pMsg = (SRpcMsg *)connection;
+int32_t qwBuildAndSendQueryRsp(SQWConnInfo *pConn, int32_t code) {
   SQueryTableRsp rsp = {.code = code};
   
   int32_t contLen = tSerializeSQueryTableRsp(NULL, 0, &rsp);
@@ -54,8 +55,8 @@ int32_t qwBuildAndSendQueryRsp(void *connection, int32_t code) {
 
   SRpcMsg rpcRsp = {
     .msgType = TDMT_VND_QUERY_RSP,
-    .handle  = pMsg->handle,
-    .ahandle = pMsg->ahandle,
+    .handle  = pConn->handle,
+    .ahandle = pConn->ahandle,
     .pCont   = msg,
     .contLen = contLen,
     .code    = code,
@@ -66,15 +67,14 @@ int32_t qwBuildAndSendQueryRsp(void *connection, int32_t code) {
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t qwBuildAndSendReadyRsp(void *connection, int32_t code) {
-  SRpcMsg *pMsg = (SRpcMsg *)connection;
+int32_t qwBuildAndSendReadyRsp(SQWConnInfo *pConn, int32_t code) {
   SResReadyRsp *pRsp = (SResReadyRsp *)rpcMallocCont(sizeof(SResReadyRsp));
   pRsp->code = code;
 
   SRpcMsg rpcRsp = {
     .msgType = TDMT_VND_RES_READY_RSP,
-    .handle  = pMsg->handle,
-    .ahandle = pMsg->ahandle,
+    .handle  = pConn->handle,
+    .ahandle = NULL,
     .pCont   = pRsp,
     .contLen = sizeof(*pRsp),
     .code    = code,
@@ -85,15 +85,15 @@ int32_t qwBuildAndSendReadyRsp(void *connection, int32_t code) {
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t qwBuildAndSendHbRsp(SRpcMsg *pMsg, SSchedulerHbRsp *pStatus, int32_t code) {
+int32_t qwBuildAndSendHbRsp(SQWConnInfo *pConn, SSchedulerHbRsp *pStatus, int32_t code) {
   int32_t contLen = tSerializeSSchedulerHbRsp(NULL, 0, pStatus);
   void *pRsp = rpcMallocCont(contLen);
   tSerializeSSchedulerHbRsp(pRsp, contLen, pStatus);
 
   SRpcMsg rpcRsp = {
     .msgType = TDMT_VND_QUERY_HEARTBEAT_RSP,
-    .handle  = pMsg->handle,
-    .ahandle = pMsg->ahandle,
+    .handle  = pConn->handle,
+    .ahandle = pConn->ahandle,
     .pCont   = pRsp,
     .contLen = contLen,
     .code    = code,
@@ -104,9 +104,7 @@ int32_t qwBuildAndSendHbRsp(SRpcMsg *pMsg, SSchedulerHbRsp *pStatus, int32_t cod
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t qwBuildAndSendFetchRsp(void *connection, SRetrieveTableRsp *pRsp, int32_t dataLength, int32_t code) {
-  SRpcMsg *pMsg = (SRpcMsg *)connection;
-  
+int32_t qwBuildAndSendFetchRsp(SQWConnInfo *pConn, SRetrieveTableRsp *pRsp, int32_t dataLength, int32_t code) {
   if (NULL == pRsp) {
     pRsp = (SRetrieveTableRsp *)rpcMallocCont(sizeof(SRetrieveTableRsp));
     memset(pRsp, 0, sizeof(SRetrieveTableRsp));
@@ -115,8 +113,8 @@ int32_t qwBuildAndSendFetchRsp(void *connection, SRetrieveTableRsp *pRsp, int32_
 
   SRpcMsg rpcRsp = {
     .msgType = TDMT_VND_FETCH_RSP,
-    .handle  = pMsg->handle,
-    .ahandle = pMsg->ahandle,
+    .handle  = pConn->handle,
+    .ahandle = pConn->ahandle,
     .pCont   = pRsp,
     .contLen = sizeof(*pRsp) + dataLength,
     .code    = code,
@@ -127,14 +125,14 @@ int32_t qwBuildAndSendFetchRsp(void *connection, SRetrieveTableRsp *pRsp, int32_
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t qwBuildAndSendCancelRsp(SRpcMsg *pMsg, int32_t code) {
+int32_t qwBuildAndSendCancelRsp(SQWConnInfo *pConn, int32_t code) {
   STaskCancelRsp *pRsp = (STaskCancelRsp *)rpcMallocCont(sizeof(STaskCancelRsp));
   pRsp->code = code;
 
   SRpcMsg rpcRsp = {
     .msgType = TDMT_VND_CANCEL_TASK_RSP,
-    .handle  = pMsg->handle,
-    .ahandle = pMsg->ahandle,
+    .handle  = pConn->handle,
+    .ahandle = pConn->ahandle,
     .pCont   = pRsp,
     .contLen = sizeof(*pRsp),
     .code    = code,
@@ -144,15 +142,14 @@ int32_t qwBuildAndSendCancelRsp(SRpcMsg *pMsg, int32_t code) {
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t qwBuildAndSendDropRsp(void *connection, int32_t code) {
-  SRpcMsg *pMsg = (SRpcMsg *)connection;
+int32_t qwBuildAndSendDropRsp(SQWConnInfo *pConn, int32_t code) {
   STaskDropRsp *pRsp = (STaskDropRsp *)rpcMallocCont(sizeof(STaskDropRsp));
   pRsp->code = code;
 
   SRpcMsg rpcRsp = {
     .msgType = TDMT_VND_DROP_TASK_RSP,
-    .handle  = pMsg->handle,
-    .ahandle = pMsg->ahandle,
+    .handle  = pConn->handle,
+    .ahandle = pConn->ahandle,
     .pCont   = pRsp,
     .contLen = sizeof(*pRsp),
     .code    = code,
@@ -234,8 +231,7 @@ int32_t qwBuildAndSendShowFetchRsp(SRpcMsg *pMsg, SVShowTablesFetchReq* pFetchRe
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t qwBuildAndSendCQueryMsg(QW_FPARAMS_DEF, void *connection) {
-  SRpcMsg *pMsg = (SRpcMsg *)connection;
+int32_t qwBuildAndSendCQueryMsg(QW_FPARAMS_DEF, SQWConnInfo *pConn) {
   SQueryContinueReq * req = (SQueryContinueReq *)rpcMallocCont(sizeof(SQueryContinueReq));
   if (NULL == req) {
     QW_SCH_TASK_ELOG("rpcMallocCont %d failed", (int32_t)sizeof(SQueryContinueReq));
@@ -248,12 +244,12 @@ int32_t qwBuildAndSendCQueryMsg(QW_FPARAMS_DEF, void *connection) {
   req->taskId = tId;
 
   SRpcMsg pNewMsg = {
-      .handle = pMsg->handle,
-      .ahandle = pMsg->ahandle,
-      .msgType = TDMT_VND_QUERY_CONTINUE,
-      .pCont = req,
-      .contLen = sizeof(SQueryContinueReq),
-      .code = 0,
+    .handle  = pConn->handle,
+    .ahandle = pConn->ahandle,
+    .msgType = TDMT_VND_QUERY_CONTINUE,
+    .pCont   = req,
+    .contLen = sizeof(SQueryContinueReq),
+    .code    = 0,
   };
 
   int32_t code = tmsgPutToQueue(&mgmt->msgCb, QUERY_QUEUE, &pNewMsg);
@@ -268,6 +264,35 @@ int32_t qwBuildAndSendCQueryMsg(QW_FPARAMS_DEF, void *connection) {
   return TSDB_CODE_SUCCESS;
 }
 
+
+int32_t qwRegisterBrokenLinkArg(QW_FPARAMS_DEF, SQWConnInfo *pConn) {
+  STaskDropReq * req = (STaskDropReq *)rpcMallocCont(sizeof(STaskDropReq));
+  if (NULL == req) {
+    QW_SCH_TASK_ELOG("rpcMallocCont %d failed", (int32_t)sizeof(STaskDropReq));
+    QW_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }  
+
+  req->header.vgId = htonl(mgmt->nodeId);
+  req->sId = htobe64(sId);
+  req->queryId = htobe64(qId);
+  req->taskId = htobe64(tId);
+  req->refId = htobe64(rId);
+  
+  SRpcMsg pMsg = {
+    .handle  = pConn->handle,
+    .ahandle = pConn->ahandle,
+    .msgType = TDMT_VND_DROP_TASK,
+    .pCont   = req,
+    .contLen = sizeof(STaskDropReq),
+    .code    = TSDB_CODE_RPC_NETWORK_UNAVAIL,
+  };
+  
+  rpcRegisterBrokenLinkArg(&pMsg);
+
+  return TSDB_CODE_SUCCESS;
+}
+
+
 int32_t qWorkerProcessQueryMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
   if (NULL == node || NULL == qWorkerMgmt || NULL == pMsg) {
     QW_ERR_RET(TSDB_CODE_QRY_INVALID_INPUT);
@@ -294,10 +319,12 @@ int32_t qWorkerProcessQueryMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
   uint64_t tId = msg->taskId;
   int64_t  rId = msg->refId;
 
-  SQWMsg qwMsg = {.node = node, .msg = msg->msg + msg->sqlLen, .msgLen = msg->phyLen, .connection = pMsg};
+  SQWMsg qwMsg = {.node = node, .msg = msg->msg + msg->sqlLen, .msgLen = msg->phyLen};
+  qwMsg.connInfo.handle = pMsg->handle;
+  qwMsg.connInfo.ahandle = pMsg->ahandle;
 
   char* sql = strndup(msg->msg, msg->sqlLen);
-  QW_SCH_TASK_DLOG("processQuery start, node:%p, sql:%s", node, sql);
+  QW_SCH_TASK_DLOG("processQuery start, node:%p, handle:%p, sql:%s", node, pMsg->handle, sql);
   taosMemoryFreeClear(sql);
 
   QW_ERR_RET(qwProcessQuery(QW_FPARAMS(), &qwMsg, msg->taskType));
@@ -326,9 +353,11 @@ int32_t qWorkerProcessCQueryMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
   uint64_t tId = msg->taskId;
   int64_t rId = 0;
 
-  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0, .connection = pMsg};
+  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0};
+  qwMsg.connInfo.handle = pMsg->handle;
+  qwMsg.connInfo.ahandle = pMsg->ahandle;
 
-  QW_SCH_TASK_DLOG("processCQuery start, node:%p", node);
+  QW_SCH_TASK_DLOG("processCQuery start, node:%p, handle:%p", node, pMsg->handle);
 
   QW_ERR_RET(qwProcessCQuery(QW_FPARAMS(), &qwMsg));
 
@@ -358,9 +387,11 @@ int32_t qWorkerProcessReadyMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg){
   uint64_t tId = msg->taskId;
   int64_t rId = 0;
 
-  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0, .connection = pMsg};
+  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0};
+  qwMsg.connInfo.handle = pMsg->handle;
+  qwMsg.connInfo.ahandle = pMsg->ahandle;
 
-  QW_SCH_TASK_DLOG("processReady start, node:%p", node);
+  QW_SCH_TASK_DLOG("processReady start, node:%p, handle:%p", node, pMsg->handle);
 
   QW_ERR_RET(qwProcessReady(QW_FPARAMS(), &qwMsg));
 
@@ -418,9 +449,11 @@ int32_t qWorkerProcessFetchMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
   uint64_t tId = msg->taskId;
   int64_t rId = 0;
 
-  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0, .connection = pMsg};
+  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0};
+  qwMsg.connInfo.handle = pMsg->handle;
+  qwMsg.connInfo.ahandle = pMsg->ahandle;
 
-  QW_SCH_TASK_DLOG("processFetch start, node:%p", node);
+  QW_SCH_TASK_DLOG("processFetch start, node:%p, handle:%p", node, pMsg->handle);
 
   QW_ERR_RET(qwProcessFetch(QW_FPARAMS(), &qwMsg));
 
@@ -439,6 +472,7 @@ int32_t qWorkerProcessCancelMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
     return TSDB_CODE_QRY_INVALID_INPUT;
   }
 
+  SQWorkerMgmt *mgmt = (SQWorkerMgmt *)qWorkerMgmt;
   int32_t code = 0;
   STaskCancelReq *msg = pMsg->pCont;
   if (NULL == msg || pMsg->contLen < sizeof(*msg)) {
@@ -451,11 +485,21 @@ int32_t qWorkerProcessCancelMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
   msg->taskId = be64toh(msg->taskId);
   msg->refId = be64toh(msg->refId);
 
+  uint64_t sId = msg->sId;
+  uint64_t qId = msg->queryId;
+  uint64_t tId = msg->taskId;
+  int64_t  rId = msg->refId;
+
+  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0};
+  qwMsg.connInfo.handle = pMsg->handle;
+  qwMsg.connInfo.ahandle = pMsg->ahandle;
+
   //QW_ERR_JRET(qwCancelTask(qWorkerMgmt, msg->sId, msg->queryId, msg->taskId));
 
 _return:
 
-  QW_ERR_RET(qwBuildAndSendCancelRsp(pMsg, code));
+  QW_ERR_RET(qwBuildAndSendCancelRsp(&qwMsg.connInfo, code));
+  QW_SCH_TASK_DLOG("cancel rsp send, handle:%p, code:%x - %s", qwMsg.connInfo.handle, code, tstrerror(code));
 
   return TSDB_CODE_SUCCESS;
 }
@@ -484,9 +528,15 @@ int32_t qWorkerProcessDropMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
   uint64_t tId = msg->taskId;
   int64_t  rId = msg->refId;
 
-  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0, .connection = pMsg};
+  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0};
+  qwMsg.connInfo.handle = pMsg->handle;
+  qwMsg.connInfo.ahandle = pMsg->ahandle;
 
-  QW_SCH_TASK_DLOG("processDrop start, node:%p", node);
+  if (TSDB_CODE_RPC_NETWORK_UNAVAIL == pMsg->code) {
+    QW_SCH_TASK_DLOG("receive drop task due to network broken, error:%s", tstrerror(pMsg->code));    
+  }
+
+  QW_SCH_TASK_DLOG("processDrop start, node:%p, handle:%p", node, pMsg->handle);
 
   QW_ERR_RET(qwProcessDrop(QW_FPARAMS(), &qwMsg));
 
@@ -516,9 +566,11 @@ int32_t qWorkerProcessHbMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
   }
 
   uint64_t sId = req.sId;
-  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0, .connection = pMsg};
+  SQWMsg qwMsg = {.node = node, .msg = NULL, .msgLen = 0};
+  qwMsg.connInfo.handle = pMsg->handle;
+  qwMsg.connInfo.ahandle = pMsg->ahandle;
 
-  QW_SCH_DLOG("processHb start, node:%p", node);
+  QW_SCH_DLOG("processHb start, node:%p, handle:%p", node, pMsg->handle);
 
   QW_ERR_RET(qwProcessHb(mgmt, &qwMsg, &req));
 
@@ -535,7 +587,7 @@ int32_t qWorkerProcessShowMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
 
   int32_t code = 0;
   SVShowTablesReq *pReq = pMsg->pCont;
-  QW_ERR_RET(qwBuildAndSendShowRsp(pMsg, code));
+  QW_RET(qwBuildAndSendShowRsp(pMsg, code));
 }
 
 int32_t qWorkerProcessShowFetchMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg) {
@@ -544,7 +596,7 @@ int32_t qWorkerProcessShowFetchMsg(void *node, void *qWorkerMgmt, SRpcMsg *pMsg)
   }
 
   SVShowTablesFetchReq *pFetchReq = pMsg->pCont;
-  QW_ERR_RET(qwBuildAndSendShowFetchRsp(pMsg, pFetchReq));
+  QW_RET(qwBuildAndSendShowFetchRsp(pMsg, pFetchReq));
 }
 
 
diff --git a/source/libs/qworker/test/qworkerTests.cpp b/source/libs/qworker/test/qworkerTests.cpp
index 705f0e2fbe..7179fa6984 100644
--- a/source/libs/qworker/test/qworkerTests.cpp
+++ b/source/libs/qworker/test/qworkerTests.cpp
@@ -887,8 +887,8 @@ TEST(seqTest, normalCase) {
   code = qWorkerProcessQueryMsg(mockPointer, mgmt, &queryRpc);
   ASSERT_EQ(code, 0);
 
-  code = qWorkerProcessReadyMsg(mockPointer, mgmt, &readyRpc);
-  ASSERT_EQ(code, 0);
+  //code = qWorkerProcessReadyMsg(mockPointer, mgmt, &readyRpc);
+  //ASSERT_EQ(code, 0);
 
   code = qWorkerProcessFetchMsg(mockPointer, mgmt, &fetchRpc);
   ASSERT_EQ(code, 0);
@@ -985,12 +985,12 @@ TEST(seqTest, randCase) {
       qwtBuildQueryReqMsg(&queryRpc);
       code = qWorkerProcessQueryMsg(mockPointer, mgmt, &queryRpc);
     } else if (r >= maxr/5 && r < maxr * 2/5) {
-      printf("Ready,%d\n", t++);
-      qwtBuildReadyReqMsg(&readyMsg, &readyRpc);
-      code = qWorkerProcessReadyMsg(mockPointer, mgmt, &readyRpc);
-      if (qwtTestEnableSleep) {
-        taosUsleep(1);
-      }
+      //printf("Ready,%d\n", t++);
+      //qwtBuildReadyReqMsg(&readyMsg, &readyRpc);
+      //code = qWorkerProcessReadyMsg(mockPointer, mgmt, &readyRpc);
+      //if (qwtTestEnableSleep) {
+      //  taosUsleep(1);
+      //}
     } else if (r >= maxr * 2/5 && r < maxr* 3/5) {
       printf("Fetch,%d\n", t++);
       qwtBuildFetchReqMsg(&fetchMsg, &fetchRpc);
@@ -1054,7 +1054,7 @@ TEST(seqTest, multithreadRand) {
 
   TdThread t1,t2,t3,t4,t5,t6;
   taosThreadCreate(&(t1), &thattr, queryThread, mgmt);
-  taosThreadCreate(&(t2), &thattr, readyThread, NULL);
+  //taosThreadCreate(&(t2), &thattr, readyThread, NULL);
   taosThreadCreate(&(t3), &thattr, fetchThread, NULL);
   taosThreadCreate(&(t4), &thattr, dropThread, NULL);
   taosThreadCreate(&(t5), &thattr, statusThread, NULL);
diff --git a/source/libs/scheduler/inc/schedulerInt.h b/source/libs/scheduler/inc/schedulerInt.h
index 1c40f255cf..518da6e2b8 100644
--- a/source/libs/scheduler/inc/schedulerInt.h
+++ b/source/libs/scheduler/inc/schedulerInt.h
@@ -25,6 +25,7 @@ extern "C" {
 #include "planner.h"
 #include "scheduler.h"
 #include "thash.h"
+#include "trpc.h"
 
 #define SCHEDULE_DEFAULT_MAX_JOB_NUM 1000
 #define SCHEDULE_DEFAULT_MAX_TASK_NUM 1000
@@ -44,7 +45,7 @@ typedef struct SSchTrans {
 
 typedef struct SSchHbTrans {
   SRWLatch  lock;
-  uint64_t  seqId;
+  SRpcCtx   rpcCtx;
   SSchTrans trans;
 } SSchHbTrans;
 
@@ -76,12 +77,23 @@ typedef struct SSchedulerMgmt {
   SHashObj       *hbConnections;
 } SSchedulerMgmt;
 
-typedef struct SSchCallbackParam {
-  uint64_t queryId;
-  int64_t  refId;
-  uint64_t taskId;
-  void    *transport;
-} SSchCallbackParam;
+typedef struct SSchCallbackParamHeader {
+  bool isHbParam;
+} SSchCallbackParamHeader;
+
+typedef struct SSchTaskCallbackParam {
+  SSchCallbackParamHeader head;
+  uint64_t                queryId;
+  int64_t                 refId;
+  uint64_t                taskId;
+  void                   *transport;
+} SSchTaskCallbackParam;
+
+typedef struct SSchHbCallbackParam {
+  SSchCallbackParamHeader head;
+  SQueryNodeEpId          nodeEpId;
+  void                   *transport;
+} SSchHbCallbackParam;
 
 typedef struct SSchFlowControl {
   SRWLatch  lock;
@@ -91,6 +103,11 @@ typedef struct SSchFlowControl {
   SArray   *taskList;      // Element is SSchTask*
 } SSchFlowControl;
 
+typedef struct SSchNodeInfo {
+  SQueryNodeAddr addr;
+  void          *handle;
+} SSchNodeInfo;
+
 typedef struct SSchLevel {
   int32_t         level;
   int8_t          status;
@@ -116,7 +133,7 @@ typedef struct SSchTask {
   SQueryNodeAddr       succeedAddr;    // task executed success node address
   int8_t               candidateIdx;   // current try condidation index
   SArray              *candidateAddrs; // condidate node addresses, element is SQueryNodeAddr
-  SArray              *execAddrs;      // all tried node for current task, element is SQueryNodeAddr
+  SArray              *execNodes;      // all tried node for current task, element is SSchNodeInfo
   SQueryProfileSummary summary;        // task execution summary
   int32_t              childReady;     // child task ready number
   SArray              *children;       // the datasource tasks,from which to fetch the result, element is SQueryTask*
@@ -178,6 +195,8 @@ extern SSchedulerMgmt schMgmt;
 #define SCH_GET_TASK_STATUS(task) atomic_load_8(&(task)->status)
 #define SCH_GET_TASK_STATUS_STR(task) jobTaskStatusStr(SCH_GET_TASK_STATUS(task))
 
+#define SCH_GET_TASK_HANDLE(_task) ((_task) ? (_task)->handle : NULL)
+#define SCH_SET_TASK_HANDLE(_task, _handle) ((_task)->handle = (_handle))
 
 #define SCH_SET_JOB_STATUS(job, st) atomic_store_8(&(job)->status, st)
 #define SCH_GET_JOB_STATUS(job) atomic_load_8(&(job)->status)
@@ -205,6 +224,8 @@ extern SSchedulerMgmt schMgmt;
   qError("QID:0x%" PRIx64 ",TID:0x%" PRIx64 " " param, pJob->queryId, SCH_TASK_ID(pTask), __VA_ARGS__)
 #define SCH_TASK_DLOG(param, ...) \
   qDebug("QID:0x%" PRIx64 ",TID:0x%" PRIx64 " " param, pJob->queryId, SCH_TASK_ID(pTask), __VA_ARGS__)
+#define SCH_TASK_DLOGL(param, ...) \
+  qDebugL("QID:0x%" PRIx64 ",TID:0x%" PRIx64 " " param, pJob->queryId, SCH_TASK_ID(pTask), __VA_ARGS__)
 #define SCH_TASK_WLOG(param, ...) \
   qWarn("QID:0x%" PRIx64 ",TID:0x%" PRIx64 " " param, pJob->queryId, SCH_TASK_ID(pTask), __VA_ARGS__)
 
@@ -228,6 +249,8 @@ int32_t schLaunchTasksInFlowCtrlList(SSchJob *pJob, SSchTask *pTask);
 int32_t schLaunchTaskImpl(SSchJob *pJob, SSchTask *pTask);
 int32_t schFetchFromRemote(SSchJob *pJob);
 int32_t schProcessOnTaskFailure(SSchJob *pJob, SSchTask *pTask, int32_t errCode);
+int32_t schBuildAndSendHbMsg(SQueryNodeEpId *nodeEpId);
+int32_t schCloneSMsgSendInfo(void *src, void **dst);
 
 
 #ifdef __cplusplus
diff --git a/source/libs/scheduler/src/scheduler.c b/source/libs/scheduler/src/scheduler.c
index 9e120041af..5af13d97ca 100644
--- a/source/libs/scheduler/src/scheduler.c
+++ b/source/libs/scheduler/src/scheduler.c
@@ -18,6 +18,7 @@
 #include "schedulerInt.h"
 #include "tmsg.h"
 #include "tref.h"
+#include "trpc.h"
 
 SSchedulerMgmt schMgmt = {0};
 
@@ -56,16 +57,36 @@ int32_t schInitTask(SSchJob *pJob, SSchTask *pTask, SSubplan *pPlan, SSchLevel *
   pTask->level = pLevel;
   SCH_SET_TASK_STATUS(pTask, JOB_TASK_STATUS_NOT_START);
   pTask->taskId = schGenTaskId();
-  pTask->execAddrs = taosArrayInit(SCH_MAX_CANDIDATE_EP_NUM, sizeof(SQueryNodeAddr));
-  if (NULL == pTask->execAddrs) {
-    SCH_TASK_ELOG("taosArrayInit %d exec addrs failed", SCH_MAX_CANDIDATE_EP_NUM);
+  pTask->execNodes = taosArrayInit(SCH_MAX_CANDIDATE_EP_NUM, sizeof(SSchNodeInfo));
+  if (NULL == pTask->execNodes) {
+    SCH_TASK_ELOG("taosArrayInit %d execNodes failed", SCH_MAX_CANDIDATE_EP_NUM);
     SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
   }
 
   return TSDB_CODE_SUCCESS;
 }
 
-void schFreeTask(SSchTask *pTask) {
+void schFreeRpcCtx(SRpcCtx *pCtx) {
+  if (NULL == pCtx) {
+    return;
+  }
+  void *pIter = taosHashIterate(pCtx->args, NULL);
+  while (pIter) {
+    SRpcCtxVal *ctxVal = (SRpcCtxVal *)pIter;
+
+    (*ctxVal->freeFunc)(ctxVal->val);
+    
+    pIter = taosHashIterate(pCtx->args, pIter);
+  }
+  
+  taosHashCleanup(pCtx->args);
+
+  if (pCtx->brokenVal.freeFunc) {
+    (*pCtx->brokenVal.freeFunc)(pCtx->brokenVal.val);
+  }
+}
+
+void schFreeTask(SSchTask* pTask) {
   if (pTask->candidateAddrs) {
     taosArrayDestroy(pTask->candidateAddrs);
   }
@@ -80,8 +101,8 @@ void schFreeTask(SSchTask *pTask) {
     taosArrayDestroy(pTask->parents);
   }
 
-  if (pTask->execAddrs) {
-    taosArrayDestroy(pTask->execAddrs);
+  if (pTask->execNodes) {
+    taosArrayDestroy(pTask->execNodes);
   }
 }
 
@@ -99,31 +120,66 @@ static FORCE_INLINE bool schJobNeedToStop(SSchJob *pJob, int8_t *pStatus) {
 int32_t schValidateTaskReceivedMsgType(SSchJob *pJob, SSchTask *pTask, int32_t msgType) {
   int32_t lastMsgType = SCH_GET_TASK_LASTMSG_TYPE(pTask);
   int32_t taskStatus = SCH_GET_TASK_STATUS(pTask);
-
+  int32_t reqMsgType = msgType - 1;
   switch (msgType) {
-    case TDMT_VND_CREATE_TABLE_RSP:
-    case TDMT_VND_SUBMIT_RSP:
-    case TDMT_VND_QUERY_RSP:
+    case TDMT_SCH_LINK_BROKEN:
+      return TSDB_CODE_SUCCESS;
+    case TDMT_VND_QUERY_RSP:  // query_rsp may be processed later than ready_rsp
+      if (lastMsgType != reqMsgType &&  -1 != lastMsgType && TDMT_VND_FETCH != lastMsgType) {
+        SCH_TASK_DLOG("rsp msg type mis-match, last sent msgType:%s, rspType:%s", TMSG_INFO(lastMsgType), TMSG_INFO(msgType));
+      }
+      
+      if (taskStatus != JOB_TASK_STATUS_EXECUTING && taskStatus != JOB_TASK_STATUS_PARTIAL_SUCCEED) {
+        SCH_TASK_DLOG("rsp msg conflicted with task status, status:%s, rspType:%s", jobTaskStatusStr(taskStatus), TMSG_INFO(msgType));
+      }
+    
+      SCH_SET_TASK_LASTMSG_TYPE(pTask, -1);
+      return TSDB_CODE_SUCCESS;
     case TDMT_VND_RES_READY_RSP:
-    case TDMT_VND_FETCH_RSP:
-    case TDMT_VND_DROP_TASK:
-      if (lastMsgType != (msgType - 1)) {
-        SCH_TASK_ELOG("rsp msg type mis-match, last sent msgType:%s, rspType:%s", TMSG_INFO(lastMsgType),
-                      TMSG_INFO(msgType));
+      reqMsgType = TDMT_VND_QUERY;
+      if (lastMsgType != reqMsgType && -1 != lastMsgType) {
+        SCH_TASK_ELOG("rsp msg type mis-match, last sent msgType:%s, rspType:%s", (lastMsgType > 0 ? TMSG_INFO(lastMsgType) : "null"), TMSG_INFO(msgType));
         SCH_ERR_RET(TSDB_CODE_SCH_STATUS_ERROR);
       }
-
+      
       if (taskStatus != JOB_TASK_STATUS_EXECUTING && taskStatus != JOB_TASK_STATUS_PARTIAL_SUCCEED) {
         SCH_TASK_ELOG("rsp msg conflicted with task status, status:%s, rspType:%s", jobTaskStatusStr(taskStatus), TMSG_INFO(msgType));
         SCH_ERR_RET(TSDB_CODE_SCH_STATUS_ERROR);
       }
 
+      SCH_SET_TASK_LASTMSG_TYPE(pTask, -1);
+      return TSDB_CODE_SUCCESS;
+    case TDMT_VND_FETCH_RSP:
+      if (lastMsgType != reqMsgType &&  -1 != lastMsgType) {
+        SCH_TASK_ELOG("rsp msg type mis-match, last sent msgType:%s, rspType:%s", TMSG_INFO(lastMsgType), TMSG_INFO(msgType));
+        SCH_ERR_RET(TSDB_CODE_SCH_STATUS_ERROR);
+      }
+      
+      if (taskStatus != JOB_TASK_STATUS_EXECUTING && taskStatus != JOB_TASK_STATUS_PARTIAL_SUCCEED) {
+        SCH_TASK_ELOG("rsp msg conflicted with task status, status:%s, rspType:%s", jobTaskStatusStr(taskStatus), TMSG_INFO(msgType));
+        SCH_ERR_RET(TSDB_CODE_SCH_STATUS_ERROR);
+      }
+      
+      SCH_SET_TASK_LASTMSG_TYPE(pTask, -1);
+      return TSDB_CODE_SUCCESS;
+    case TDMT_VND_CREATE_TABLE_RSP:
+    case TDMT_VND_SUBMIT_RSP:
       break;
     default:
       SCH_TASK_ELOG("unknown rsp msg, type:%s, status:%s", TMSG_INFO(msgType), jobTaskStatusStr(taskStatus));
       SCH_ERR_RET(TSDB_CODE_QRY_INVALID_INPUT);
   }
 
+  if (lastMsgType != reqMsgType) {
+    SCH_TASK_ELOG("rsp msg type mis-match, last sent msgType:%s, rspType:%s", TMSG_INFO(lastMsgType), TMSG_INFO(msgType));
+    SCH_ERR_RET(TSDB_CODE_SCH_STATUS_ERROR);
+  }
+  
+  if (taskStatus != JOB_TASK_STATUS_EXECUTING && taskStatus != JOB_TASK_STATUS_PARTIAL_SUCCEED) {
+    SCH_TASK_ELOG("rsp msg conflicted with task status, status:%s, rspType:%s", jobTaskStatusStr(taskStatus), TMSG_INFO(msgType));
+    SCH_ERR_RET(TSDB_CODE_SCH_STATUS_ERROR);
+  }
+
   SCH_SET_TASK_LASTMSG_TYPE(pTask, -1);
 
   return TSDB_CODE_SUCCESS;
@@ -299,12 +355,16 @@ int32_t schRecordTaskSucceedNode(SSchJob *pJob, SSchTask *pTask) {
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t schRecordTaskExecNode(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr) {
-  if (NULL == taosArrayPush(pTask->execAddrs, addr)) {
-    SCH_TASK_ELOG("taosArrayPush addr to execAddr list failed, errno:%d", errno);
+int32_t schRecordTaskExecNode(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr, void *handle) {
+  SSchNodeInfo nodeInfo = {.addr = *addr, .handle = handle};
+  
+  if (NULL == taosArrayPush(pTask->execNodes, &nodeInfo)) {
+    SCH_TASK_ELOG("taosArrayPush nodeInfo to execNodes list failed, errno:%d", errno);
     SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
   }
 
+  SCH_TASK_DLOG("task execNode recorded, handle:%p", handle);
+
   return TSDB_CODE_SUCCESS;
 }
 
@@ -632,53 +692,23 @@ int32_t schHandleTaskRetry(SSchJob *pJob, SSchTask *pTask) {
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t schUpdateHbConnection(SQueryNodeEpId *epId, SSchHbTrans *trans) {
+int32_t schUpdateHbConnection(SQueryNodeEpId *epId, SSchTrans *trans) {
   int32_t      code = 0;
   SSchHbTrans *hb = NULL;
 
-  while (true) {
-    hb = taosHashGet(schMgmt.hbConnections, epId, sizeof(SQueryNodeEpId));
-    if (NULL == hb) {
-      code = taosHashPut(schMgmt.hbConnections, epId, sizeof(SQueryNodeEpId), trans, sizeof(SSchHbTrans));
-      if (code) {
-        if (HASH_NODE_EXIST(code)) {
-          continue;
-        }
-
-        qError("taosHashPut hb trans failed, nodeId:%d, fqdn:%s, port:%d", epId->nodeId, epId->ep.fqdn, epId->ep.port);
-        SCH_ERR_RET(code);
-      }
-
-      qDebug("hb connection updated, seqId:%" PRIx64 ", sId:%" PRIx64
-             ", nodeId:%d, fqdn:%s, port:%d, instance:%p, connection:%p",
-             trans->seqId, schMgmt.sId, epId->nodeId, epId->ep.fqdn, epId->ep.port, trans->trans.transInst,
-             trans->trans.transHandle);
-
-      return TSDB_CODE_SUCCESS;
-    }
-
-    break;
+  hb = taosHashGet(schMgmt.hbConnections, epId, sizeof(SQueryNodeEpId));
+  if (NULL == hb) {
+    qError("taosHashGet hb connection failed, nodeId:%d, fqdn:%s, port:%d", epId->nodeId, epId->ep.fqdn, epId->ep.port);
+    SCH_ERR_RET(TSDB_CODE_QRY_APP_ERROR);
   }
 
   SCH_LOCK(SCH_WRITE, &hb->lock);
-
-  if (hb->seqId >= trans->seqId) {
-    qDebug("hb trans seqId is old, seqId:%" PRId64 ", currentId:%" PRId64 ", nodeId:%d, fqdn:%s, port:%d", trans->seqId,
-           hb->seqId, epId->nodeId, epId->ep.fqdn, epId->ep.port);
-
-    SCH_UNLOCK(SCH_WRITE, &hb->lock);
-    return TSDB_CODE_SUCCESS;
-  }
-
-  hb->seqId = trans->seqId;
-  memcpy(&hb->trans, &trans->trans, sizeof(trans->trans));
-
+  memcpy(&hb->trans, trans, sizeof(*trans));
   SCH_UNLOCK(SCH_WRITE, &hb->lock);
 
-  qDebug("hb connection updated, seqId:%" PRIx64 ", sId:%" PRIx64
-         ", nodeId:%d, fqdn:%s, port:%d, instance:%p, connection:%p",
-         trans->seqId, schMgmt.sId, epId->nodeId, epId->ep.fqdn, epId->ep.port, trans->trans.transInst,
-         trans->trans.transHandle);
+  qDebug("hb connection updated, sId:%" PRIx64 ", nodeId:%d, fqdn:%s, port:%d, instance:%p, handle:%p",
+         schMgmt.sId, epId->nodeId, epId->ep.fqdn, epId->ep.port, trans->transInst,
+         trans->transHandle);
 
   return TSDB_CODE_SUCCESS;
 }
@@ -993,7 +1023,7 @@ int32_t schHandleResponseMsg(SSchJob *pJob, SSchTask *pTask, int32_t msgType, ch
           SCH_ERR_JRET(TSDB_CODE_QRY_INVALID_INPUT);
         }
         
-        SCH_ERR_JRET(schBuildAndSendMsg(pJob, pTask, NULL, TDMT_VND_RES_READY));
+        //SCH_ERR_JRET(schBuildAndSendMsg(pJob, pTask, NULL, TDMT_VND_RES_READY));
         
         break;
     }
@@ -1041,6 +1071,10 @@ int32_t schHandleResponseMsg(SSchJob *pJob, SSchTask *pTask, int32_t msgType, ch
       SCH_ERR_JRET(TSDB_CODE_SCH_INTERNAL_ERROR);
       break;
     }
+    case TDMT_SCH_LINK_BROKEN:
+      SCH_TASK_ELOG("link broken received, error:%x - %s", rspCode, tstrerror(rspCode));
+      SCH_ERR_JRET(rspCode);
+      break;
     default:
       SCH_TASK_ELOG("unknown rsp msg, type:%d, status:%s", msgType, SCH_GET_TASK_STATUS_STR(pTask));
       SCH_ERR_JRET(TSDB_CODE_QRY_INVALID_INPUT);
@@ -1055,12 +1089,12 @@ _return:
 
 int32_t schHandleCallback(void *param, const SDataBuf *pMsg, int32_t msgType, int32_t rspCode) {
   int32_t            code = 0;
-  SSchCallbackParam *pParam = (SSchCallbackParam *)param;
+  SSchTaskCallbackParam *pParam = (SSchTaskCallbackParam *)param;
   SSchTask          *pTask = NULL;
 
   SSchJob *pJob = schAcquireJob(pParam->refId);
   if (NULL == pJob) {
-    qError("QID:0x%" PRIx64 ",TID:0x%" PRIx64 "taosAcquireRef job failed, may be dropped, refId:%" PRIx64,
+    qWarn("QID:0x%" PRIx64 ",TID:0x%" PRIx64 "taosAcquireRef job failed, may be dropped, refId:%" PRIx64,
            pParam->queryId, pParam->taskId, pParam->refId);
     SCH_ERR_JRET(TSDB_CODE_QRY_JOB_FREED);
   }
@@ -1078,9 +1112,9 @@ int32_t schHandleCallback(void *param, const SDataBuf *pMsg, int32_t msgType, in
   }
 
   pTask = *task;
-  SCH_TASK_DLOG("rsp msg received, type:%s, code:%s", TMSG_INFO(msgType), tstrerror(rspCode));
+  SCH_TASK_DLOG("rsp msg received, type:%s, handle:%p, code:%s", TMSG_INFO(msgType), pMsg->handle, tstrerror(rspCode));
 
-  pTask->handle = pMsg->handle;
+  SCH_SET_TASK_HANDLE(pTask, pMsg->handle);  
   SCH_ERR_JRET(schHandleResponseMsg(pJob, pTask, msgType, pMsg->pData, pMsg->len, rspCode));
 
 _return:
@@ -1114,7 +1148,7 @@ int32_t schHandleReadyCallback(void *param, const SDataBuf *pMsg, int32_t code)
 }
 
 int32_t schHandleDropCallback(void *param, const SDataBuf *pMsg, int32_t code) {
-  SSchCallbackParam *pParam = (SSchCallbackParam *)param;
+  SSchTaskCallbackParam *pParam = (SSchTaskCallbackParam *)param;
   qDebug("QID:%" PRIx64 ",TID:%" PRIx64 " drop task rsp received, code:%x", pParam->queryId, pParam->taskId, code);
 }
 
@@ -1125,24 +1159,22 @@ int32_t schHandleHbCallback(void *param, const SDataBuf *pMsg, int32_t code) {
   }
 
   SSchedulerHbRsp rsp = {0};
-
-  SSchCallbackParam *pParam = (SSchCallbackParam *)param;
-
   if (tDeserializeSSchedulerHbRsp(pMsg->pData, pMsg->len, &rsp)) {
     qError("invalid hb rsp msg, size:%d", pMsg->len);
     SCH_ERR_RET(TSDB_CODE_QRY_INVALID_INPUT);
   }
 
-  if (rsp.seqId != (uint64_t)-1) {
-    SSchHbTrans trans = {0};
-    trans.seqId = rsp.seqId;
-    trans.trans.transInst = pParam->transport;
-    trans.trans.transHandle = pMsg->handle;
+  SSchTaskCallbackParam *pParam = (SSchTaskCallbackParam *)param;
 
-    SCH_RET(schUpdateHbConnection(&rsp.epId, &trans));
-  }
+  SSchTrans trans = {0};
+  trans.transInst = pParam->transport;
+  trans.transHandle = pMsg->handle;
+
+  SCH_ERR_RET(schUpdateHbConnection(&rsp.epId, &trans));
 
   int32_t taskNum = (int32_t)taosArrayGetSize(rsp.taskStatus);
+  qDebug("%d task status in hb rsp, nodeId:%d, fqdn:%s, port:%d", taskNum, rsp.epId.nodeId, rsp.epId.ep.fqdn, rsp.epId.ep.port);
+
   for (int32_t i = 0; i < taskNum; ++i) {
     STaskStatus *taskStatus = taosArrayGet(rsp.taskStatus, i);
 
@@ -1155,6 +1187,8 @@ int32_t schHandleHbCallback(void *param, const SDataBuf *pMsg, int32_t code) {
     }
 
     // TODO
+    
+    SCH_JOB_DLOG("TID:0x%" PRIx64 " task status in server: %s", taskStatus->taskId, jobTaskStatusStr(taskStatus->status));
 
     schReleaseJob(taskStatus->refId);
   }
@@ -1166,6 +1200,26 @@ _return:
   SCH_RET(code);
 }
 
+int32_t schHandleLinkBrokenCallback(void *param, const SDataBuf *pMsg, int32_t code) {
+  SSchCallbackParamHeader *head = (SSchCallbackParamHeader *)param;
+  rpcReleaseHandle(pMsg->handle, TAOS_CONN_CLIENT);
+
+  qDebug("handle %p is broken", pMsg->handle);
+
+  if (head->isHbParam) {
+    SSchHbCallbackParam *hbParam = (SSchHbCallbackParam *)param;
+    SSchTrans trans = {.transInst = hbParam->transport, .transHandle = NULL};
+    SCH_ERR_RET(schUpdateHbConnection(&hbParam->nodeEpId, &trans));
+
+    SCH_ERR_RET(schBuildAndSendHbMsg(&hbParam->nodeEpId));
+  } else {
+    SCH_ERR_RET(schHandleCallback(param, pMsg, TDMT_SCH_LINK_BROKEN, code));
+  }
+
+  return TSDB_CODE_SUCCESS;
+}
+
+
 int32_t schGetCallbackFp(int32_t msgType, __async_send_cb_fn_t *fp) {
   switch (msgType) {
     case TDMT_VND_CREATE_TABLE:
@@ -1189,6 +1243,9 @@ int32_t schGetCallbackFp(int32_t msgType, __async_send_cb_fn_t *fp) {
     case TDMT_VND_QUERY_HEARTBEAT:
       *fp = schHandleHbCallback;
       break;
+    case TDMT_SCH_LINK_BROKEN:
+      *fp = schHandleLinkBrokenCallback;
+      break;
     default:
       qError("unknown msg type for callback, msgType:%d", msgType);
       SCH_ERR_RET(TSDB_CODE_QRY_APP_ERROR);
@@ -1197,8 +1254,322 @@ int32_t schGetCallbackFp(int32_t msgType, __async_send_cb_fn_t *fp) {
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t schAsyncSendMsg(SSchJob *pJob, SSchTask *pTask, void *transport, SEpSet *epSet, int32_t msgType, void *msg,
-                        uint32_t msgSize) {
+void schFreeRpcCtxVal(const void *arg) {
+  if (NULL == arg) {
+    return;
+  }
+  
+  SMsgSendInfo* pMsgSendInfo = (SMsgSendInfo *)arg;
+  taosMemoryFreeClear(pMsgSendInfo->param);
+  taosMemoryFreeClear(pMsgSendInfo);
+}
+
+int32_t schMakeTaskCallbackParam(SSchJob *pJob, SSchTask *pTask, void **pParam) {
+  SSchTaskCallbackParam *param = taosMemoryCalloc(1, sizeof(SSchTaskCallbackParam));
+  if (NULL == param) {
+    SCH_TASK_ELOG("calloc %d failed", (int32_t)sizeof(SSchTaskCallbackParam));
+    SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  param->queryId = pJob->queryId;
+  param->refId = pJob->refId;
+  param->taskId = SCH_TASK_ID(pTask);
+  param->transport = pJob->transport;
+
+  *pParam = param;
+
+  return TSDB_CODE_SUCCESS;
+}
+
+int32_t schMakeHbCallbackParam(SSchJob *pJob, SSchTask *pTask, void **pParam) {
+  SSchHbCallbackParam *param = taosMemoryCalloc(1, sizeof(SSchHbCallbackParam));
+  if (NULL == param) {
+    SCH_TASK_ELOG("calloc %d failed", (int32_t)sizeof(SSchHbCallbackParam));
+    SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  param->head.isHbParam = true;
+
+  SQueryNodeAddr *addr = taosArrayGet(pTask->candidateAddrs, pTask->candidateIdx);
+
+  param->nodeEpId.nodeId = addr->nodeId;
+  memcpy(&param->nodeEpId.ep, SCH_GET_CUR_EP(addr), sizeof(SEp));
+  param->transport = pJob->transport;
+
+  *pParam = param;
+
+  return TSDB_CODE_SUCCESS;
+}
+
+
+int32_t schMakeBrokenLinkVal(SSchJob *pJob, SSchTask *pTask, SRpcBrokenlinkVal *brokenVal, bool isHb) {
+  int32_t code = 0;
+  SMsgSendInfo* pMsgSendInfo = NULL;
+  
+  pMsgSendInfo = taosMemoryCalloc(1, sizeof(SMsgSendInfo));
+  if (NULL == pMsgSendInfo) {
+    SCH_TASK_ELOG("calloc %d failed", (int32_t)sizeof(SMsgSendInfo));
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  if (isHb) {
+    SCH_ERR_JRET(schMakeHbCallbackParam(pJob, pTask, &pMsgSendInfo->param));
+  } else {
+    SCH_ERR_JRET(schMakeTaskCallbackParam(pJob, pTask, &pMsgSendInfo->param));
+  }
+
+  int32_t msgType = TDMT_SCH_LINK_BROKEN;
+  __async_send_cb_fn_t fp = NULL;
+  SCH_ERR_JRET(schGetCallbackFp(msgType, &fp));
+  
+  pMsgSendInfo->fp = fp;
+
+  brokenVal->msgType = msgType;
+  brokenVal->val = pMsgSendInfo;
+  brokenVal->clone = schCloneSMsgSendInfo;
+  brokenVal->freeFunc = schFreeRpcCtxVal;
+  
+  return TSDB_CODE_SUCCESS;
+
+_return:
+
+  taosMemoryFreeClear(pMsgSendInfo->param);
+  taosMemoryFreeClear(pMsgSendInfo);
+
+  SCH_RET(code);
+}
+
+int32_t schMakeQueryRpcCtx(SSchJob *pJob, SSchTask *pTask, SRpcCtx *pCtx) {
+  int32_t code = 0;
+  SSchTaskCallbackParam *param = NULL;
+  SMsgSendInfo* pMsgSendInfo = NULL;
+
+  pCtx->args = taosHashInit(1, taosGetDefaultHashFunction(TSDB_DATA_TYPE_INT), false, HASH_ENTRY_LOCK);
+  if (NULL == pCtx->args) {
+    SCH_TASK_ELOG("taosHashInit %d RpcCtx failed", 1);
+    SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+  
+  pMsgSendInfo = taosMemoryCalloc(1, sizeof(SMsgSendInfo));
+  if (NULL == pMsgSendInfo) {
+    SCH_TASK_ELOG("calloc %d failed", (int32_t)sizeof(SMsgSendInfo));
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  param = taosMemoryCalloc(1, sizeof(SSchTaskCallbackParam));
+  if (NULL == param) {
+    SCH_TASK_ELOG("calloc %d failed", (int32_t)sizeof(SSchTaskCallbackParam));
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  int32_t msgType = TDMT_VND_RES_READY_RSP;
+  __async_send_cb_fn_t fp = NULL;
+  SCH_ERR_JRET(schGetCallbackFp(TDMT_VND_RES_READY, &fp));
+
+  param->queryId = pJob->queryId;
+  param->refId = pJob->refId;
+  param->taskId = SCH_TASK_ID(pTask);
+  param->transport = pJob->transport;
+  
+  pMsgSendInfo->param = param;
+  pMsgSendInfo->fp = fp;
+
+  SRpcCtxVal ctxVal = {.val = pMsgSendInfo, .clone = schCloneSMsgSendInfo, .freeFunc = schFreeRpcCtxVal};
+  if (taosHashPut(pCtx->args, &msgType, sizeof(msgType), &ctxVal, sizeof(ctxVal))) {
+    SCH_TASK_ELOG("taosHashPut msg %d to rpcCtx failed", msgType);
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  SCH_ERR_JRET(schMakeBrokenLinkVal(pJob, pTask, &pCtx->brokenVal, false));
+
+  return TSDB_CODE_SUCCESS;
+
+_return:
+
+  taosHashCleanup(pCtx->args);
+  taosMemoryFreeClear(param);
+  taosMemoryFreeClear(pMsgSendInfo);
+
+  SCH_RET(code);
+}
+
+int32_t schMakeHbRpcCtx(SSchJob *pJob, SSchTask *pTask, SRpcCtx *pCtx) {
+  int32_t code = 0;
+  SSchHbCallbackParam *param = NULL;
+  SMsgSendInfo* pMsgSendInfo = NULL;
+  SQueryNodeAddr *addr = taosArrayGet(pTask->candidateAddrs, pTask->candidateIdx);
+  SQueryNodeEpId  epId = {0};
+
+  epId.nodeId = addr->nodeId;
+  memcpy(&epId.ep, SCH_GET_CUR_EP(addr), sizeof(SEp));
+
+  pCtx->args = taosHashInit(1, taosGetDefaultHashFunction(TSDB_DATA_TYPE_INT), false, HASH_ENTRY_LOCK);
+  if (NULL == pCtx->args) {
+    SCH_TASK_ELOG("taosHashInit %d RpcCtx failed", 1);
+    SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+  
+  pMsgSendInfo = taosMemoryCalloc(1, sizeof(SMsgSendInfo));
+  if (NULL == pMsgSendInfo) {
+    SCH_TASK_ELOG("calloc %d failed", (int32_t)sizeof(SMsgSendInfo));
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  param = taosMemoryCalloc(1, sizeof(SSchHbCallbackParam));
+  if (NULL == param) {
+    SCH_TASK_ELOG("calloc %d failed", (int32_t)sizeof(SSchHbCallbackParam));
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  int32_t msgType = TDMT_VND_QUERY_HEARTBEAT_RSP;
+  __async_send_cb_fn_t fp = NULL;
+  SCH_ERR_JRET(schGetCallbackFp(TDMT_VND_QUERY_HEARTBEAT, &fp));
+
+  param->nodeEpId = epId;
+  param->transport = pJob->transport;
+  
+  pMsgSendInfo->param = param;
+  pMsgSendInfo->fp = fp;
+
+  SRpcCtxVal ctxVal = {.val = pMsgSendInfo, .clone = schCloneSMsgSendInfo, .freeFunc = schFreeRpcCtxVal};
+  if (taosHashPut(pCtx->args, &msgType, sizeof(msgType), &ctxVal, sizeof(ctxVal))) {
+    SCH_TASK_ELOG("taosHashPut msg %d to rpcCtx failed", msgType);
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  SCH_ERR_JRET(schMakeBrokenLinkVal(pJob, pTask, &pCtx->brokenVal, true));
+
+  return TSDB_CODE_SUCCESS;
+
+_return:
+
+  taosHashCleanup(pCtx->args);
+  taosMemoryFreeClear(param);
+  taosMemoryFreeClear(pMsgSendInfo);
+
+  SCH_RET(code);
+}
+
+
+int32_t schRegisterHbConnection(SSchJob *pJob, SSchTask *pTask, SQueryNodeEpId *epId, bool *exist) {
+  int32_t      code = 0;
+  SSchHbTrans hb = {0};
+
+  hb.trans.transInst = pJob->transport;
+  
+  SCH_ERR_RET(schMakeHbRpcCtx(pJob, pTask, &hb.rpcCtx));
+
+  code = taosHashPut(schMgmt.hbConnections, epId, sizeof(SQueryNodeEpId), &hb, sizeof(SSchHbTrans));
+  if (code) {
+    schFreeRpcCtx(&hb.rpcCtx);
+    
+    if (HASH_NODE_EXIST(code)) {
+      *exist = true;
+      return TSDB_CODE_SUCCESS;
+    }
+
+    qError("taosHashPut hb trans failed, nodeId:%d, fqdn:%s, port:%d", epId->nodeId, epId->ep.fqdn, epId->ep.port);
+    SCH_ERR_RET(code);
+  }
+
+  return TSDB_CODE_SUCCESS;
+}
+
+
+
+int32_t schCloneCallbackParam(SSchCallbackParamHeader *pSrc, SSchCallbackParamHeader **pDst) {
+  if (pSrc->isHbParam) {
+    SSchHbCallbackParam *dst = taosMemoryMalloc(sizeof(SSchHbCallbackParam));
+    if (NULL == dst) {
+      qError("malloc SSchHbCallbackParam failed");
+      SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+    }
+
+    memcpy(dst, pSrc, sizeof(*dst));
+    *pDst = (SSchCallbackParamHeader *)dst;
+
+    return TSDB_CODE_SUCCESS;
+  }
+
+  SSchTaskCallbackParam *dst = taosMemoryMalloc(sizeof(SSchTaskCallbackParam));
+  if (NULL == dst) {
+    qError("malloc SSchTaskCallbackParam failed");
+    SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+  
+  memcpy(dst, pSrc, sizeof(*dst));
+  *pDst = (SSchCallbackParamHeader *)dst;
+  
+  return TSDB_CODE_SUCCESS;
+}
+
+int32_t schCloneSMsgSendInfo(void *src, void **dst) {
+  SMsgSendInfo *pSrc = src;
+  int32_t code = 0;
+  SMsgSendInfo *pDst = taosMemoryMalloc(sizeof(*pSrc));
+  if (NULL == pDst) {
+    qError("malloc SMsgSendInfo for rpcCtx failed, len:%d", (int32_t)sizeof(*pSrc));
+    SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  memcpy(pDst, pSrc, sizeof(*pSrc));
+  pDst->param = NULL;
+
+  SCH_ERR_JRET(schCloneCallbackParam(pSrc->param, (SSchCallbackParamHeader **)&pDst->param));
+
+  *dst = pDst;
+
+  return TSDB_CODE_SUCCESS;
+  
+_return:
+
+  taosMemoryFreeClear(pDst);
+  SCH_RET(code);
+}
+
+int32_t schCloneHbRpcCtx(SRpcCtx *pSrc, SRpcCtx *pDst) {
+  int32_t code = 0;
+  memcpy(&pDst->brokenVal, &pSrc->brokenVal, sizeof(pSrc->brokenVal));
+  pDst->brokenVal.val = NULL;
+  
+  SCH_ERR_RET(schCloneSMsgSendInfo(pSrc->brokenVal.val, &pDst->brokenVal.val));
+
+  pDst->args = taosHashInit(1, taosGetDefaultHashFunction(TSDB_DATA_TYPE_INT), false, HASH_ENTRY_LOCK);
+  if (NULL == pDst->args) {
+    qError("taosHashInit %d RpcCtx failed", 1);
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  SRpcCtxVal dst = {0};
+  void *pIter = taosHashIterate(pSrc->args, NULL);
+  while (pIter) {
+    SRpcCtxVal *pVal = (SRpcCtxVal *)pIter;
+    int32_t *msgType = taosHashGetKey(pIter, NULL);
+
+    dst = *pVal;
+    dst.val = NULL;
+    
+    SCH_ERR_JRET(schCloneSMsgSendInfo(pVal->val, &dst.val));
+    
+    if (taosHashPut(pDst->args, msgType, sizeof(*msgType), &dst, sizeof(dst))) {
+      qError("taosHashPut msg %d to rpcCtx failed", *msgType);
+      (*dst.freeFunc)(dst.val);
+      SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+    }
+
+    pIter = taosHashIterate(pSrc->args, pIter);
+  }
+
+  return TSDB_CODE_SUCCESS;
+
+_return:
+
+  schFreeRpcCtx(pDst);
+  SCH_RET(code);
+}
+
+
+int32_t schAsyncSendMsg(SSchJob *pJob, SSchTask *pTask, void *transport, SEpSet* epSet, int32_t msgType, void *msg, uint32_t msgSize, bool persistHandle, SRpcCtx *ctx) {
   int32_t code = 0;
 
   SSchTrans *trans = (SSchTrans *)transport;
@@ -1209,9 +1580,9 @@ int32_t schAsyncSendMsg(SSchJob *pJob, SSchTask *pTask, void *transport, SEpSet
     SCH_ERR_RET(TSDB_CODE_QRY_OUT_OF_MEMORY);
   }
 
-  SSchCallbackParam *param = taosMemoryCalloc(1, sizeof(SSchCallbackParam));
+  SSchTaskCallbackParam *param = taosMemoryCalloc(1, sizeof(SSchTaskCallbackParam));
   if (NULL == param) {
-    SCH_TASK_ELOG("calloc %d failed", (int32_t)sizeof(SSchCallbackParam));
+    SCH_TASK_ELOG("calloc %d failed", (int32_t)sizeof(SSchTaskCallbackParam));
     SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
   }
 
@@ -1230,8 +1601,12 @@ int32_t schAsyncSendMsg(SSchJob *pJob, SSchTask *pTask, void *transport, SEpSet
   pMsgSendInfo->msgType = msgType;
   pMsgSendInfo->fp = fp;
 
-  int64_t transporterId = 0;
-  code = asyncSendMsgToServer(trans->transInst, epSet, &transporterId, pMsgSendInfo);
+  qDebug("start to send %s msg to node[%d,%s,%d], refId:%" PRIx64 "instance:%p, handle:%p", 
+         TMSG_INFO(msgType), ntohl(((SMsgHead *)msg)->vgId), epSet->eps[epSet->inUse].fqdn, epSet->eps[epSet->inUse].port, 
+         pJob->refId, trans->transInst, trans->transHandle);
+  
+  int64_t  transporterId = 0;
+  code = asyncSendMsgToServerExt(trans->transInst, epSet, &transporterId, pMsgSendInfo, persistHandle, ctx);
   if (code) {
     SCH_ERR_JRET(code);
   }
@@ -1246,11 +1621,103 @@ _return:
   SCH_RET(code);
 }
 
+int32_t schBuildAndSendHbMsg(SQueryNodeEpId *nodeEpId) {
+  SSchedulerHbReq req = {0};
+  int32_t code = 0;
+  SRpcCtx rpcCtx = {0};
+  SSchTrans trans = {0};
+  int32_t msgType = TDMT_VND_QUERY_HEARTBEAT;
+
+  req.header.vgId = htonl(nodeEpId->nodeId);
+  req.sId = schMgmt.sId;
+  memcpy(&req.epId, nodeEpId, sizeof(SQueryNodeEpId));
+
+  SSchHbTrans *hb = taosHashGet(schMgmt.hbConnections, nodeEpId, sizeof(SQueryNodeEpId));
+  if (NULL == hb) {
+    qError("taosHashGet hb connection failed, nodeId:%d, fqdn:%s, port:%d", nodeEpId->nodeId, nodeEpId->ep.fqdn, nodeEpId->ep.port);
+    SCH_ERR_RET(code);
+  }
+
+  SCH_LOCK(SCH_WRITE, &hb->lock);
+  code = schCloneHbRpcCtx(&hb->rpcCtx, &rpcCtx);
+  memcpy(&trans, &hb->trans, sizeof(trans));
+  SCH_UNLOCK(SCH_WRITE, &hb->lock);
+  
+  SCH_ERR_RET(code);
+  
+  int32_t msgSize = tSerializeSSchedulerHbReq(NULL, 0, &req);
+  if (msgSize < 0) {
+    qError("tSerializeSSchedulerHbReq hbReq failed, size:%d", msgSize);
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+  void *msg = taosMemoryCalloc(1, msgSize);
+  if (NULL == msg) {
+    qError("calloc hb req %d failed", msgSize);
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+  
+  if (tSerializeSSchedulerHbReq(msg, msgSize, &req) < 0) {
+    qError("tSerializeSSchedulerHbReq hbReq failed, size:%d", msgSize);
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  SMsgSendInfo *pMsgSendInfo = taosMemoryCalloc(1, sizeof(SMsgSendInfo));
+  if (NULL == pMsgSendInfo) {
+    qError("calloc SMsgSendInfo failed");
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  SSchTaskCallbackParam *param = taosMemoryCalloc(1, sizeof(SSchTaskCallbackParam));
+  if (NULL == param) {
+    qError("calloc SSchTaskCallbackParam failed");
+    SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
+  }
+
+  __async_send_cb_fn_t fp = NULL;
+  SCH_ERR_JRET(schGetCallbackFp(msgType, &fp));
+
+  param->transport = trans.transInst;
+
+  pMsgSendInfo->param = param;
+  pMsgSendInfo->msgInfo.pData = msg;
+  pMsgSendInfo->msgInfo.len = msgSize;
+  pMsgSendInfo->msgInfo.handle = trans.transHandle;
+  pMsgSendInfo->msgType = msgType;
+  pMsgSendInfo->fp = fp;
+  
+  int64_t  transporterId = 0;
+  SEpSet epSet = {.inUse = 0, .numOfEps = 1};
+  memcpy(&epSet.eps[0], &nodeEpId->ep, sizeof(nodeEpId->ep));
+
+  qDebug("start to send hb msg, instance:%p, handle:%p, fqdn:%s, port:%d", trans.transInst, trans.transHandle, nodeEpId->ep.fqdn, nodeEpId->ep.port);
+  
+  code = asyncSendMsgToServerExt(trans.transInst, &epSet, &transporterId, pMsgSendInfo, true, &rpcCtx);
+  if (code) {
+    qError("fail to send hb msg, instance:%p, handle:%p, fqdn:%s, port:%d, error:%x - %s", 
+      trans.transInst, trans.transHandle, nodeEpId->ep.fqdn, nodeEpId->ep.port, code, tstrerror(code));
+    SCH_ERR_JRET(code);
+  }
+
+  qDebug("hb msg sent");
+  return TSDB_CODE_SUCCESS;
+
+_return:
+
+  taosMemoryFreeClear(msg);
+  taosMemoryFreeClear(param);
+  taosMemoryFreeClear(pMsgSendInfo);
+  schFreeRpcCtx(&rpcCtx);
+  SCH_RET(code);
+}
+
 int32_t schBuildAndSendMsg(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr, int32_t msgType) {
   uint32_t msgSize = 0;
-  void    *msg = NULL;
-  int32_t  code = 0;
-  bool     isCandidateAddr = false;
+  void *msg = NULL;
+  int32_t code = 0;
+  bool isCandidateAddr = false;
+  bool persistHandle = false;
+  SRpcCtx rpcCtx = {0};
+  
   if (NULL == addr) {
     addr = taosArrayGet(pTask->candidateAddrs, pTask->candidateIdx);
     isCandidateAddr = true;
@@ -1273,8 +1740,9 @@ int32_t schBuildAndSendMsg(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr,
     }
 
     case TDMT_VND_QUERY: {
+      SCH_ERR_RET(schMakeQueryRpcCtx(pJob, pTask, &rpcCtx));
+      
       uint32_t len = strlen(pJob->sql);
-
       msgSize = sizeof(SSubQueryMsg) + pTask->msgLen + len;
       msg = taosMemoryCalloc(1, msgSize);
       if (NULL == msg) {
@@ -1294,7 +1762,8 @@ int32_t schBuildAndSendMsg(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr,
 
       memcpy(pMsg->msg, pJob->sql, len);
       memcpy(pMsg->msg + len, pTask->msg, pTask->msgLen);
-      
+
+      persistHandle = true;
       break;
     }
 
@@ -1330,6 +1799,7 @@ int32_t schBuildAndSendMsg(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr,
       pMsg->sId = htobe64(schMgmt.sId);
       pMsg->queryId = htobe64(pJob->queryId);
       pMsg->taskId = htobe64(pTask->taskId);
+
       break;
     }
     case TDMT_VND_DROP_TASK: {
@@ -1351,6 +1821,8 @@ int32_t schBuildAndSendMsg(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr,
       break;
     }
     case TDMT_VND_QUERY_HEARTBEAT: {
+      SCH_ERR_RET(schMakeHbRpcCtx(pJob, pTask, &rpcCtx));
+    
       SSchedulerHbReq req = {0};
       req.sId = schMgmt.sId;
       req.header.vgId = addr->nodeId;
@@ -1371,6 +1843,8 @@ int32_t schBuildAndSendMsg(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr,
         SCH_JOB_ELOG("tSerializeSSchedulerHbReq hbReq failed, size:%d", msgSize);
         SCH_ERR_JRET(TSDB_CODE_QRY_OUT_OF_MEMORY);
       }
+
+      persistHandle = true;
       break;
     }
     default:
@@ -1381,11 +1855,11 @@ int32_t schBuildAndSendMsg(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr,
 
   SCH_SET_TASK_LASTMSG_TYPE(pTask, msgType);
 
-  SSchTrans trans = {.transInst = pJob->transport, .transHandle = pTask ? pTask->handle : NULL};
-  SCH_ERR_JRET(schAsyncSendMsg(pJob, pTask, &trans, &epSet, msgType, msg, msgSize));
+  SSchTrans trans = {.transInst = pJob->transport, .transHandle = SCH_GET_TASK_HANDLE(pTask)};
+  SCH_ERR_JRET(schAsyncSendMsg(pJob, pTask, &trans, &epSet, msgType, msg, msgSize, persistHandle, (rpcCtx.args ? &rpcCtx : NULL)));
 
-  if (isCandidateAddr) {
-    SCH_ERR_RET(schRecordTaskExecNode(pJob, pTask, addr));
+  if (msgType == TDMT_VND_QUERY) {
+    SCH_ERR_RET(schRecordTaskExecNode(pJob, pTask, addr, trans.transHandle));
   }
 
   return TSDB_CODE_SUCCESS;
@@ -1393,6 +1867,7 @@ int32_t schBuildAndSendMsg(SSchJob *pJob, SSchTask *pTask, SQueryNodeAddr *addr,
 _return:
 
   SCH_SET_TASK_LASTMSG_TYPE(pTask, -1);
+  schFreeRpcCtx(&rpcCtx);
 
   taosMemoryFreeClear(msg);
   SCH_RET(code);
@@ -1405,10 +1880,16 @@ int32_t schEnsureHbConnection(SSchJob *pJob, SSchTask *pTask) {
   epId.nodeId = addr->nodeId;
   memcpy(&epId.ep, SCH_GET_CUR_EP(addr), sizeof(SEp));
 
+#if 1
   SSchHbTrans *hb = taosHashGet(schMgmt.hbConnections, &epId, sizeof(SQueryNodeEpId));
   if (NULL == hb) {
-    SCH_ERR_RET(schBuildAndSendMsg(pJob, NULL, addr, TDMT_VND_QUERY_HEARTBEAT));
+    bool exist = false;
+    SCH_ERR_RET(schRegisterHbConnection(pJob, pTask, &epId, &exist));
+    if (!exist) {
+      SCH_ERR_RET(schBuildAndSendHbMsg(&epId));
+    }
   }
+#endif
 
   return TSDB_CODE_SUCCESS;
 }
@@ -1440,7 +1921,7 @@ int32_t schLaunchTaskImpl(SSchJob *pJob, SSchTask *pTask) {
                     pTask->msgLen);
       SCH_ERR_RET(code);
     } else {
-      SCH_TASK_DLOG("physical plan len:%d, %s", pTask->msgLen, pTask->msg);
+      SCH_TASK_DLOGL("physical plan len:%d, %s", pTask->msgLen, pTask->msg);
     }
   }
 
@@ -1460,6 +1941,8 @@ int32_t schLaunchTask(SSchJob *pJob, SSchTask *pTask) {
   bool    enough = false;
   int32_t code = 0;
 
+  SCH_SET_TASK_HANDLE(pTask, NULL);
+
   if (SCH_TASK_NEED_FLOW_CTRL(pJob, pTask)) {
     SCH_ERR_JRET(schCheckIncTaskFlowQuota(pJob, pTask, &enough));
 
@@ -1500,23 +1983,24 @@ int32_t schLaunchJob(SSchJob *pJob) {
 }
 
 void schDropTaskOnExecutedNode(SSchJob *pJob, SSchTask *pTask) {
-  if (NULL == pTask->execAddrs) {
+  if (NULL == pTask->execNodes) {
     SCH_TASK_DLOG("no exec address, status:%s", SCH_GET_TASK_STATUS_STR(pTask));
     return;
   }
 
-  int32_t size = (int32_t)taosArrayGetSize(pTask->execAddrs);
+  int32_t size = (int32_t)taosArrayGetSize(pTask->execNodes);
 
   if (size <= 0) {
-    SCH_TASK_DLOG("task has no exec address, no need to drop it, status:%s", SCH_GET_TASK_STATUS_STR(pTask));
+    SCH_TASK_DLOG("task has no execNodes, no need to drop it, status:%s", SCH_GET_TASK_STATUS_STR(pTask));
     return;
   }
 
-  SQueryNodeAddr *addr = NULL;
+  SSchNodeInfo *nodeInfo = NULL;
   for (int32_t i = 0; i < size; ++i) {
-    addr = (SQueryNodeAddr *)taosArrayGet(pTask->execAddrs, i);
+    nodeInfo = (SSchNodeInfo *)taosArrayGet(pTask->execNodes, i);
+    SCH_SET_TASK_HANDLE(pTask, nodeInfo->handle);
 
-    schBuildAndSendMsg(pJob, pTask, addr, TDMT_VND_DROP_TASK);
+    schBuildAndSendMsg(pJob, pTask, &nodeInfo->addr, TDMT_VND_DROP_TASK);
   }
 
   SCH_TASK_DLOG("task has %d exec address", size);
diff --git a/source/libs/scheduler/test/schedulerTests.cpp b/source/libs/scheduler/test/schedulerTests.cpp
index b2fbf33b8a..cf04b06579 100644
--- a/source/libs/scheduler/test/schedulerTests.cpp
+++ b/source/libs/scheduler/test/schedulerTests.cpp
@@ -387,7 +387,7 @@ void *schtCreateFetchRspThread(void *param) {
 
 void *schtFetchRspThread(void *aa) {
   SDataBuf dataBuf = {0};
-  SSchCallbackParam* param = NULL;
+  SSchTaskCallbackParam* param = NULL;
 
   while (!schtTestStop) {
     if (0 == atomic_val_compare_exchange_32(&schtStartFetch, 1, 0)) {
@@ -396,7 +396,7 @@ void *schtFetchRspThread(void *aa) {
 
     taosUsleep(1);
     
-    param = (SSchCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
+    param = (SSchTaskCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
 
     param->queryId = schtQueryId;  
     param->taskId = schtFetchTaskId;
@@ -449,7 +449,7 @@ void* schtRunJobThread(void *aa) {
   schtSetAsyncSendMsgToServer();
 
   SSchJob *pJob = NULL;
-  SSchCallbackParam *param = NULL;
+  SSchTaskCallbackParam *param = NULL;
   SHashObj *execTasks = NULL;
   SDataBuf dataBuf = {0};
   uint32_t jobFinished = 0;
@@ -484,7 +484,7 @@ void* schtRunJobThread(void *aa) {
       pIter = taosHashIterate(pJob->execTasks, pIter);
     }    
 
-    param = (SSchCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
+    param = (SSchTaskCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
     param->refId = queryJobRefId;
     param->queryId = pJob->queryId;   
 
@@ -504,7 +504,7 @@ void* schtRunJobThread(void *aa) {
     }    
 
 
-    param = (SSchCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
+    param = (SSchTaskCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
     param->refId = queryJobRefId;
     param->queryId = pJob->queryId;   
     
@@ -524,7 +524,7 @@ void* schtRunJobThread(void *aa) {
     }  
 
 
-    param = (SSchCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
+    param = (SSchTaskCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
     param->refId = queryJobRefId;
     param->queryId = pJob->queryId;   
 
@@ -544,7 +544,7 @@ void* schtRunJobThread(void *aa) {
     }    
 
 
-    param = (SSchCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
+    param = (SSchTaskCallbackParam *)taosMemoryCalloc(1, sizeof(*param));
     param->refId = queryJobRefId;
     param->queryId = pJob->queryId;   
 
@@ -713,6 +713,116 @@ TEST(queryTest, normalCase) {
   schedulerDestroy();
 }
 
+TEST(queryTest, readyFirstCase) {
+  void *mockPointer = (void *)0x1;
+  char *clusterId = "cluster1";
+  char *dbname = "1.db1";
+  char *tablename = "table1";
+  SVgroupInfo vgInfo = {0};
+  int64_t job = 0;
+  SQueryPlan dag;
+
+  memset(&dag, 0, sizeof(dag));
+
+  SArray *qnodeList = taosArrayInit(1, sizeof(SEp));
+
+  SEp qnodeAddr = {0};
+  strcpy(qnodeAddr.fqdn, "qnode0.ep");
+  qnodeAddr.port = 6031;
+  taosArrayPush(qnodeList, &qnodeAddr);
+  
+  int32_t code = schedulerInit(NULL);
+  ASSERT_EQ(code, 0);
+
+  schtBuildQueryDag(&dag);
+
+  schtSetPlanToString();
+  schtSetExecNode();
+  schtSetAsyncSendMsgToServer();
+  
+  code = schedulerAsyncExecJob(mockPointer, qnodeList, &dag, "select * from tb", &job);
+  ASSERT_EQ(code, 0);
+
+  
+  SSchJob *pJob = schAcquireJob(job);
+
+  void *pIter = taosHashIterate(pJob->execTasks, NULL);
+  while (pIter) {
+    SSchTask *task = *(SSchTask **)pIter;
+
+    SResReadyRsp rsp = {0};
+    code = schHandleResponseMsg(pJob, task, TDMT_VND_RES_READY_RSP, (char *)&rsp, sizeof(rsp), 0);
+    printf("code:%d", code);
+    ASSERT_EQ(code, 0);
+    pIter = taosHashIterate(pJob->execTasks, pIter);
+  }  
+  
+  pIter = taosHashIterate(pJob->execTasks, NULL);
+  while (pIter) {
+    SSchTask *task = *(SSchTask **)pIter;
+
+    SQueryTableRsp rsp = {0};
+    code = schHandleResponseMsg(pJob, task, TDMT_VND_QUERY_RSP, (char *)&rsp, sizeof(rsp), 0);
+    
+    ASSERT_EQ(code, 0);
+    pIter = taosHashIterate(pJob->execTasks, pIter);
+  }    
+
+  pIter = taosHashIterate(pJob->execTasks, NULL);
+  while (pIter) {
+    SSchTask *task = *(SSchTask **)pIter;
+
+    SResReadyRsp rsp = {0};
+    code = schHandleResponseMsg(pJob, task, TDMT_VND_RES_READY_RSP, (char *)&rsp, sizeof(rsp), 0);
+    ASSERT_EQ(code, 0);
+    
+    pIter = taosHashIterate(pJob->execTasks, pIter);
+  }  
+
+  pIter = taosHashIterate(pJob->execTasks, NULL);
+  while (pIter) {
+    SSchTask *task = *(SSchTask **)pIter;
+
+    SQueryTableRsp rsp = {0};
+    code = schHandleResponseMsg(pJob, task, TDMT_VND_QUERY_RSP, (char *)&rsp, sizeof(rsp), 0);
+    
+    ASSERT_EQ(code, 0);
+    pIter = taosHashIterate(pJob->execTasks, pIter);
+  }    
+
+
+
+  TdThreadAttr thattr;
+  taosThreadAttrInit(&thattr);
+
+  TdThread thread1;
+  taosThreadCreate(&(thread1), &thattr, schtCreateFetchRspThread, &job);
+
+  void *data = NULL;  
+  code = schedulerFetchRows(job, &data);
+  ASSERT_EQ(code, 0);
+
+  SRetrieveTableRsp *pRsp = (SRetrieveTableRsp *)data;
+  ASSERT_EQ(pRsp->completed, 1);
+  ASSERT_EQ(pRsp->numOfRows, 10);
+  taosMemoryFreeClear(data);
+
+  data = NULL;
+  code = schedulerFetchRows(job, &data);
+  ASSERT_EQ(code, 0);
+  ASSERT_TRUE(data == NULL);
+
+  schReleaseJob(job);
+
+  schedulerFreeJob(job);
+
+  schtFreeQueryDag(&dag);
+
+  schedulerDestroy();
+}
+
+
+
 TEST(queryTest, flowCtrlCase) {
   void *mockPointer = (void *)0x1;
   char *clusterId = "cluster1";
diff --git a/source/libs/transport/inc/transComm.h b/source/libs/transport/inc/transComm.h
index eaca66aeab..1b8cbb0f04 100644
--- a/source/libs/transport/inc/transComm.h
+++ b/source/libs/transport/inc/transComm.h
@@ -158,7 +158,8 @@ typedef struct {
   char secured : 2;
   char spi : 2;
 
-  uint32_t code;  // del later
+  uint64_t ahandle;  // ahandle assigned by client
+  uint32_t code;     // del later
   uint32_t msgType;
   int32_t  msgLen;
   uint8_t  content[0];  // message body starts from here
@@ -182,7 +183,7 @@ typedef struct {
 #pragma pack(pop)
 
 typedef enum { Normal, Quit, Release, Register } STransMsgType;
-typedef enum { ConnNormal, ConnAcquire, ConnRelease, ConnBroken } ConnStatus;
+typedef enum { ConnNormal, ConnAcquire, ConnRelease, ConnBroken, ConnInPool } ConnStatus;
 
 #define container_of(ptr, type, member) ((type*)((char*)(ptr)-offsetof(type, member)))
 #define RPC_RESERVE_SIZE (sizeof(STranConnCtx))
@@ -277,6 +278,7 @@ void  transCtxCleanup(STransCtx* ctx);
 void  transCtxClear(STransCtx* ctx);
 void  transCtxMerge(STransCtx* dst, STransCtx* src);
 void* transCtxDumpVal(STransCtx* ctx, int32_t key);
+void* transCtxDumpBrokenlinkVal(STransCtx* ctx, int32_t* msgType);
 
 // queue sending msgs
 typedef struct {
@@ -295,20 +297,25 @@ void transQueueInit(STransQueue* queue, void (*freeFunc)(const void* arg));
  * if queue'size > 1, return false; else return true
  */
 bool transQueuePush(STransQueue* queue, void* arg);
+/*
+ * the size of queue
+ */
+int32_t transQueueSize(STransQueue* queue);
 /*
  * pop head from queue
  */
-
 void* transQueuePop(STransQueue* queue);
 /*
- * get head from queue
+ * get ith from queue
  */
-void* transQueueGet(STransQueue* queue);
-
+void* transQueueGet(STransQueue* queue, int i);
+/*
+ * rm ith from queue
+ */
+void* transQueueRm(STransQueue* queue, int i);
 /*
  * queue empty or not
  */
-
 bool transQueueEmpty(STransQueue* queue);
 /*
  * clear queue
diff --git a/source/libs/transport/src/transCli.c b/source/libs/transport/src/transCli.c
index a0e8af1db9..d9c288a39b 100644
--- a/source/libs/transport/src/transCli.c
+++ b/source/libs/transport/src/transCli.c
@@ -25,12 +25,11 @@ typedef struct SCliConn {
   void*        hostThrd;
   SConnBuffer  readBuf;
   void*        data;
-  // SArray*      cliMsgs;
-  STransQueue cliMsgs;
-  queue       conn;
-  uint64_t    expireTime;
-  int         hThrdIdx;
-  STransCtx   ctx;
+  STransQueue  cliMsgs;
+  queue        conn;
+  uint64_t     expireTime;
+  int          hThrdIdx;
+  STransCtx    ctx;
 
   bool       broken;   // link broken or not
   ConnStatus status;   //
@@ -54,6 +53,7 @@ typedef struct SCliMsg {
   queue          q;
   uint64_t       st;
   STransMsgType  type;
+  int            sent;  //(0: no send, 1: alread sent)
 } SCliMsg;
 
 typedef struct SCliThrdObj {
@@ -136,6 +136,8 @@ static void         destroyThrdObj(SCliThrdObj* pThrd);
 #define CONN_SHOULD_RELEASE(conn, head)                                                  \
   do {                                                                                   \
     if ((head)->release == 1 && (head->msgLen) == sizeof(*head)) {                       \
+      uint64_t ahandle = head->ahandle;                                                  \
+      CONN_GET_MSGCTX_BY_AHANDLE(conn, ahandle);                                         \
       conn->status = ConnRelease;                                                        \
       transClearBuffer(&conn->readBuf);                                                  \
       transFreeMsg(transContFromHead((char*)head));                                      \
@@ -147,10 +149,40 @@ static void         destroyThrdObj(SCliThrdObj* pThrd);
         SCliThrdObj* thrd = conn->hostThrd;                                              \
         addConnToPool(thrd->pool, conn);                                                 \
       }                                                                                  \
+      destroyCmsg(pMsg);                                                                 \
       return;                                                                            \
     }                                                                                    \
   } while (0)
 
+#define CONN_GET_MSGCTX_BY_AHANDLE(conn, ahandle)                    \
+  do {                                                               \
+    int i = 0, sz = transQueueSize(&conn->cliMsgs);                  \
+    for (; i < sz; i++) {                                            \
+      pMsg = transQueueGet(&conn->cliMsgs, i);                       \
+      if (pMsg != NULL && pMsg->ctx != NULL && (uint64_t)pMsg->ctx->ahandle == ahandle) { \
+        break;                                                       \
+      }                                                              \
+    }                                                                \
+    if (i == sz) {                                                   \
+      pMsg = NULL;                                                   \
+    } else {                                                         \
+      pMsg = transQueueRm(&conn->cliMsgs, i);                        \
+    }                                                                \
+  } while (0)
+#define CONN_GET_NEXT_SENDMSG(conn)                 \
+  do {                                              \
+    int i = 0;                                      \
+    do {                                            \
+      pCliMsg = transQueueGet(&conn->cliMsgs, i++); \
+      if (pCliMsg && 0 == pCliMsg->sent) {          \
+        break;                                      \
+      }                                             \
+    } while (pCliMsg != NULL);                      \
+    if (pCliMsg == NULL) {                          \
+      goto _RETURN;                                 \
+    }                                               \
+  } while (0)
+
 #define CONN_HANDLE_THREAD_QUIT(thrd) \
   do {                                \
     if (thrd->quit) {                 \
@@ -173,8 +205,10 @@ static void         destroyThrdObj(SCliThrdObj* pThrd);
       transRefCliHandle(conn);        \
     }                                 \
   } while (0)
-#define CONN_NO_PERSIST_BY_APP(conn) ((conn)->status == ConnNormal && T_REF_VAL_GET(conn) == 1)
-
+#define CONN_NO_PERSIST_BY_APP(conn) \
+  (((conn)->status == ConnNormal || (conn)->status == ConnInPool) && T_REF_VAL_GET(conn) == 1)
+#define CONN_RELEASE_BY_SERVER(conn) \
+  (((conn)->status == ConnRelease || (conn)->status == ConnInPool) && T_REF_VAL_GET(conn) == 1)
 #define REQUEST_NO_RESP(msg) ((msg)->noResp == 1)
 #define REQUEST_PERSIS_HANDLE(msg) ((msg)->persistHandle == 1)
 #define REQUEST_RELEASE_HANDLE(cmsg) ((cmsg)->type == Release)
@@ -183,10 +217,13 @@ static void* cliWorkThread(void* arg);
 
 bool cliMaySendCachedMsg(SCliConn* conn) {
   if (!transQueueEmpty(&conn->cliMsgs)) {
+    SCliMsg* pCliMsg = NULL;
+    CONN_GET_NEXT_SENDMSG(conn);
     cliSend(conn);
-    return true;
   }
   return false;
+_RETURN:
+  return false;
 }
 void cliHandleResp(SCliConn* conn) {
   SCliThrdObj* pThrd = conn->hostThrd;
@@ -203,15 +240,38 @@ void cliHandleResp(SCliConn* conn) {
   transMsg.msgType = pHead->msgType;
   transMsg.ahandle = NULL;
 
+  SCliMsg*       pMsg = NULL;
+  STransConnCtx* pCtx = NULL;
   CONN_SHOULD_RELEASE(conn, pHead);
 
-  SCliMsg* pMsg = transQueuePop(&conn->cliMsgs);
-
-  STransConnCtx* pCtx = pMsg ? pMsg->ctx : NULL;
-  if (pMsg == NULL && !CONN_NO_PERSIST_BY_APP(conn)) {
-    transMsg.ahandle = transCtxDumpVal(&conn->ctx, transMsg.msgType);
+  if (CONN_NO_PERSIST_BY_APP(conn)) {
+    pMsg = transQueuePop(&conn->cliMsgs);
+    pCtx = pMsg ? pMsg->ctx : NULL;
+    if (pMsg == NULL && !CONN_NO_PERSIST_BY_APP(conn)) {
+      transMsg.ahandle = transCtxDumpVal(&conn->ctx, transMsg.msgType);
+      if (transMsg.ahandle == NULL) {
+        transMsg.ahandle = transCtxDumpBrokenlinkVal(&conn->ctx, (int32_t*)&(transMsg.msgType));
+      }
+      tDebug("cli conn %p construct ahandle %p, persist: 0", conn, transMsg.ahandle);
+    } else {
+      transMsg.ahandle = pCtx ? pCtx->ahandle : NULL;
+      tDebug("cli conn %p get ahandle %p, persist: 0", conn, transMsg.ahandle);
+    }
   } else {
-    transMsg.ahandle = pCtx ? pCtx->ahandle : NULL;
+    uint64_t ahandle = (uint64_t)pHead->ahandle;
+    CONN_GET_MSGCTX_BY_AHANDLE(conn, ahandle);
+    if (pMsg == NULL) {
+      transMsg.ahandle = transCtxDumpVal(&conn->ctx, transMsg.msgType);
+      tDebug("cli conn %p construct ahandle %p by %d, persist: 1", conn, transMsg.ahandle, transMsg.msgType);
+      if (!CONN_RELEASE_BY_SERVER(conn) && transMsg.ahandle == NULL) {
+        transMsg.ahandle = transCtxDumpBrokenlinkVal(&conn->ctx, (int32_t*)&(transMsg.msgType));
+        tDebug("cli conn %p construct ahandle %p due brokenlink, persist: 1", conn, transMsg.ahandle);
+      }
+    } else {
+      pCtx = pMsg ? pMsg->ctx : NULL;
+      transMsg.ahandle = pCtx ? pCtx->ahandle : NULL;
+      tDebug("cli conn %p get ahandle %p, persist: 1", conn, transMsg.ahandle);
+    }
   }
   // buf's mem alread translated to transMsg.pCont
   transClearBuffer(&conn->readBuf);
@@ -232,6 +292,11 @@ void cliHandleResp(SCliConn* conn) {
     // transUnrefCliHandle(conn);
     return;
   }
+  if (CONN_RELEASE_BY_SERVER(conn) && transMsg.ahandle == NULL) {
+    tTrace("except, server continue send while cli ignore it");
+    // transUnrefCliHandle(conn);
+    return;
+  }
 
   if (pCtx == NULL || pCtx->pSem == NULL) {
     tTrace("%s cli conn %p handle resp", pTransInst->label, conn);
@@ -256,41 +321,54 @@ void cliHandleResp(SCliConn* conn) {
   if (!uv_is_active((uv_handle_t*)&pThrd->timer) && pTransInst->idleTime > 0) {
     // uv_timer_start((uv_timer_t*)&pThrd->timer, cliTimeoutCb, CONN_PERSIST_TIME(pRpc->idleTime) / 2, 0);
   }
-_RETURN:
-  return;
 }
 
 void cliHandleExcept(SCliConn* pConn) {
   if (transQueueEmpty(&pConn->cliMsgs)) {
-    if (pConn->broken == true || CONN_NO_PERSIST_BY_APP(pConn)) {
+    if (pConn->broken == true && CONN_NO_PERSIST_BY_APP(pConn)) {
+      tTrace("%s cli conn %p handle except, persist:0", CONN_GET_INST_LABEL(pConn), pConn);
       transUnrefCliHandle(pConn);
       return;
     }
   }
   SCliThrdObj* pThrd = pConn->hostThrd;
   STrans*      pTransInst = pThrd->pTransInst;
-
+  bool         once = false;
   do {
     SCliMsg* pMsg = transQueuePop(&pConn->cliMsgs);
-
+    if (pMsg == NULL && once) {
+      break;
+    }
     STransConnCtx* pCtx = pMsg ? pMsg->ctx : NULL;
 
     STransMsg transMsg = {0};
     transMsg.code = TSDB_CODE_RPC_NETWORK_UNAVAIL;
     transMsg.msgType = pMsg ? pMsg->msg.msgType + 1 : 0;
     transMsg.ahandle = NULL;
+    transMsg.handle = pConn;
 
     if (pMsg == NULL && !CONN_NO_PERSIST_BY_APP(pConn)) {
       transMsg.ahandle = transCtxDumpVal(&pConn->ctx, transMsg.msgType);
+      tDebug("%s cli conn %p construct ahandle %p by %s", CONN_GET_INST_LABEL(pConn), pConn, transMsg.ahandle,
+             TMSG_INFO(transMsg.msgType));
+      if (transMsg.ahandle == NULL) {
+        transMsg.ahandle = transCtxDumpBrokenlinkVal(&pConn->ctx, (int32_t*)&(transMsg.msgType));
+        tDebug("%s cli conn %p construct ahandle %p due to brokenlink", CONN_GET_INST_LABEL(pConn), pConn,
+               transMsg.ahandle);
+      }
     } else {
       transMsg.ahandle = pCtx ? pCtx->ahandle : NULL;
     }
 
     if (pCtx == NULL || pCtx->pSem == NULL) {
-      tTrace("%s cli conn %p handle resp", pTransInst->label, pConn);
+      tTrace("%s cli conn %p handle except", pTransInst->label, pConn);
+      if (transMsg.ahandle == NULL) {
+        once = true;
+        continue;
+      }
       (pTransInst->cfp)(pTransInst->parent, &transMsg, NULL);
     } else {
-      tTrace("%s cli conn(sync) %p handle resp", pTransInst->label, pConn);
+      tTrace("%s cli conn(sync) %p handle except", pTransInst->label, pConn);
       memcpy((char*)(pCtx->pRsp), (char*)(&transMsg), sizeof(transMsg));
       tsem_post(pCtx->pSem);
     }
@@ -364,8 +442,8 @@ static SCliConn* getConnFromPool(void* pool, char* ip, uint32_t port) {
   }
   queue* h = QUEUE_HEAD(&plist->conn);
   QUEUE_REMOVE(h);
-
   SCliConn* conn = QUEUE_DATA(h, SCliConn, conn);
+  conn->status = ConnNormal;
   QUEUE_INIT(&conn->conn);
   return conn;
 }
@@ -377,7 +455,7 @@ static void addConnToPool(void* pool, SCliConn* conn) {
   conn->expireTime = taosGetTimestampMs() + CONN_PERSIST_TIME(pTransInst->idleTime);
   transCtxCleanup(&conn->ctx);
   transQueueClear(&conn->cliMsgs);
-  conn->status = ConnNormal;
+  conn->status = ConnInPool;
 
   char key[128] = {0};
   tstrncpy(key, conn->ip, strlen(conn->ip));
@@ -466,7 +544,7 @@ static void cliDestroy(uv_handle_t* handle) {
 static bool cliHandleNoResp(SCliConn* conn) {
   bool res = false;
   if (!transQueueEmpty(&conn->cliMsgs)) {
-    SCliMsg* pMsg = transQueueGet(&conn->cliMsgs);
+    SCliMsg* pMsg = transQueueGet(&conn->cliMsgs, 0);
     if (REQUEST_NO_RESP(&pMsg->msg)) {
       transQueuePop(&conn->cliMsgs);
       // taosArrayRemove(msgs, 0);
@@ -504,7 +582,11 @@ void cliSend(SCliConn* pConn) {
 
   // assert(taosArrayGetSize(pConn->cliMsgs) > 0);
   assert(!transQueueEmpty(&pConn->cliMsgs));
-  SCliMsg*       pCliMsg = transQueueGet(&pConn->cliMsgs);
+
+  SCliMsg* pCliMsg = NULL;
+  CONN_GET_NEXT_SENDMSG(pConn);
+  pCliMsg->sent = 1;
+
   STransConnCtx* pCtx = pCliMsg->ctx;
 
   SCliThrdObj* pThrd = pConn->hostThrd;
@@ -516,7 +598,9 @@ void cliSend(SCliConn* pConn) {
     pMsg->contLen = 0;
   }
   STransMsgHead* pHead = transHeadFromCont(pMsg->pCont);
-  int            msgLen = transMsgLenFromCont(pMsg->contLen);
+  pHead->ahandle = pCtx != NULL ? (uint64_t)pCtx->ahandle : 0;
+
+  int msgLen = transMsgLenFromCont(pMsg->contLen);
 
   if (!pConn->secured) {
     char* buf = taosMemoryCalloc(1, msgLen + sizeof(STransUserMsg));
@@ -555,6 +639,8 @@ void cliSend(SCliConn* pConn) {
   pConn->writeReq.data = pConn;
   uv_write(&pConn->writeReq, (uv_stream_t*)pConn->stream, &wb, 1, cliSendCb);
 
+  return;
+_RETURN:
   return;
 }
 
@@ -643,6 +729,7 @@ void cliHandleReq(SCliMsg* pMsg, SCliThrdObj* pThrd) {
     cliSend(conn);
   } else {
     conn = cliCreateConn(pThrd);
+    transCtxMerge(&conn->ctx, &pCtx->appCtx);
     transQueuePush(&conn->cliMsgs, pMsg);
 
     conn->hThrdIdx = pCtx->hThrdIdx;
diff --git a/source/libs/transport/src/transComm.c b/source/libs/transport/src/transComm.c
index 31ac1e1fbf..3078324c6b 100644
--- a/source/libs/transport/src/transComm.c
+++ b/source/libs/transport/src/transComm.c
@@ -238,12 +238,15 @@ void transCtxCleanup(STransCtx* ctx) {
     iter->freeFunc(iter->val);
     iter = taosHashIterate(ctx->args, iter);
   }
+
   taosHashCleanup(ctx->args);
+  ctx->args = NULL;
 }
 
 void transCtxMerge(STransCtx* dst, STransCtx* src) {
   if (dst->args == NULL) {
     dst->args = src->args;
+    dst->brokenVal = src->brokenVal;
     src->args = NULL;
     return;
   }
@@ -271,9 +274,20 @@ void* transCtxDumpVal(STransCtx* ctx, int32_t key) {
   if (cVal == NULL) {
     return NULL;
   }
-  char* ret = taosMemoryCalloc(1, cVal->len);
-  memcpy(ret, (char*)cVal->val, cVal->len);
-  return (void*)ret;
+  void* ret = NULL;
+  (*cVal->clone)(cVal->val, &ret);
+  return ret;
+}
+void* transCtxDumpBrokenlinkVal(STransCtx* ctx, int32_t* msgType) {
+  void* ret = NULL;
+  if (ctx->brokenVal.clone == NULL) {
+    return ret;
+  }
+  (*ctx->brokenVal.clone)(ctx->brokenVal.val, &ret);
+
+  *msgType = ctx->brokenVal.msgType;
+
+  return ret;
 }
 
 void transQueueInit(STransQueue* queue, void (*freeFunc)(const void* arg)) {
@@ -281,6 +295,9 @@ void transQueueInit(STransQueue* queue, void (*freeFunc)(const void* arg)) {
   queue->freeFunc = freeFunc;
 }
 bool transQueuePush(STransQueue* queue, void* arg) {
+  if (queue->q == NULL) {
+    return true;
+  }
   taosArrayPush(queue->q, &arg);
   if (taosArrayGetSize(queue->q) > 1) {
     return false;
@@ -288,23 +305,47 @@ bool transQueuePush(STransQueue* queue, void* arg) {
   return true;
 }
 void* transQueuePop(STransQueue* queue) {
-  if (taosArrayGetSize(queue->q) == 0) {
+  if (queue->q == NULL || taosArrayGetSize(queue->q) == 0) {
     return NULL;
   }
   void* ptr = taosArrayGetP(queue->q, 0);
   taosArrayRemove(queue->q, 0);
   return ptr;
 }
-
-void* transQueueGet(STransQueue* queue) {
-  if (taosArrayGetSize(queue->q) == 0) {
+int32_t transQueueSize(STransQueue* queue) {
+  if (queue->q == NULL) {
+    return 0;
+  }
+  return taosArrayGetSize(queue->q);
+}
+void* transQueueGet(STransQueue* queue, int i) {
+  if (queue->q == NULL || taosArrayGetSize(queue->q) == 0) {
     return NULL;
   }
-  void* ptr = taosArrayGetP(queue->q, 0);
+  if (i >= taosArrayGetSize(queue->q)) {
+    return NULL;
+  }
+
+  void* ptr = taosArrayGetP(queue->q, i);
   return ptr;
 }
+
+void* transQueueRm(STransQueue* queue, int i) {
+  if (queue->q == NULL || taosArrayGetSize(queue->q) == 0) {
+    return NULL;
+  }
+  if (i >= taosArrayGetSize(queue->q)) {
+    return NULL;
+  }
+  void* ptr = taosArrayGetP(queue->q, i);
+  taosArrayRemove(queue->q, i);
+  return ptr;
+}
+
 bool transQueueEmpty(STransQueue* queue) {
-  //
+  if (queue->q == NULL) {
+    return true;
+  }
   return taosArrayGetSize(queue->q) == 0;
 }
 void transQueueClear(STransQueue* queue) {
diff --git a/source/libs/transport/src/transSrv.c b/source/libs/transport/src/transSrv.c
index d503c5b3d3..c137657a99 100644
--- a/source/libs/transport/src/transSrv.c
+++ b/source/libs/transport/src/transSrv.c
@@ -93,25 +93,25 @@ typedef struct SServerObj {
 
 static const char* notify = "a";
 
-#define CONN_SHOULD_RELEASE(conn, head)                            \
-  do {                                                             \
-    if ((head)->release == 1 && (head->msgLen) == sizeof(*head)) { \
-      conn->status = ConnRelease;                                  \
-      transClearBuffer(&conn->readBuf);                            \
-      transFreeMsg(transContFromHead((char*)head));                \
-      tTrace("server conn %p received release request", conn);     \
-                                                                   \
-      STransMsg tmsg = {.handle = (void*)conn, .code = 0};         \
-      SSrvMsg*  srvMsg = taosMemoryCalloc(1, sizeof(SSrvMsg));               \
-      srvMsg->msg = tmsg;                                          \
-      srvMsg->type = Release;                                      \
-      srvMsg->pConn = conn;                                        \
-      if (!transQueuePush(&conn->srvMsgs, srvMsg)) {               \
-        return;                                                    \
-      }                                                            \
-      uvStartSendRespInternal(srvMsg);                             \
-      return;                                                      \
-    }                                                              \
+#define CONN_SHOULD_RELEASE(conn, head)                                     \
+  do {                                                                      \
+    if ((head)->release == 1 && (head->msgLen) == sizeof(*head)) {          \
+      conn->status = ConnRelease;                                           \
+      transClearBuffer(&conn->readBuf);                                     \
+      transFreeMsg(transContFromHead((char*)head));                         \
+      tTrace("server conn %p received release request", conn);              \
+                                                                            \
+      STransMsg tmsg = {.code = 0, .handle = (void*)conn, .ahandle = NULL}; \
+      SSrvMsg*  srvMsg = taosMemoryCalloc(1, sizeof(SSrvMsg));              \
+      srvMsg->msg = tmsg;                                                   \
+      srvMsg->type = Release;                                               \
+      srvMsg->pConn = conn;                                                 \
+      if (!transQueuePush(&conn->srvMsgs, srvMsg)) {                        \
+        return;                                                             \
+      }                                                                     \
+      uvStartSendRespInternal(srvMsg);                                      \
+      return;                                                               \
+    }                                                                       \
   } while (0)
 
 static void uvAllocConnBufferCb(uv_handle_t* handle, size_t suggested_size, uv_buf_t* buf);
@@ -190,7 +190,7 @@ static void uvHandleReq(SSrvConn* pConn) {
   transMsg.pCont = pHead->content;
   transMsg.msgType = pHead->msgType;
   transMsg.code = pHead->code;
-  transMsg.ahandle = NULL;
+  transMsg.ahandle = (void*)pHead->ahandle;
   transMsg.handle = NULL;
 
   transClearBuffer(&pConn->readBuf);
@@ -199,6 +199,7 @@ static void uvHandleReq(SSrvConn* pConn) {
     if (pHead->persist == 1) {
       pConn->status = ConnAcquire;
       transRefSrvHandle(pConn);
+      tDebug("server conn %p acquired by server app", pConn);
     }
   }
   if (pConn->status == ConnNormal && pHead->noResp == 0) {
@@ -279,7 +280,7 @@ void uvOnSendCb(uv_write_t* req, int status) {
       destroySmsg(msg);
       // send second data, just use for push
       if (!transQueueEmpty(&conn->srvMsgs)) {
-        msg = (SSrvMsg*)transQueueGet(&conn->srvMsgs);
+        msg = (SSrvMsg*)transQueueGet(&conn->srvMsgs, 0);
         if (msg->type == Register && conn->status == ConnAcquire) {
           conn->regArg.notifyCount = 0;
           conn->regArg.init = 1;
@@ -291,6 +292,11 @@ void uvOnSendCb(uv_write_t* req, int status) {
           }
           transQueuePop(&conn->srvMsgs);
           taosMemoryFree(msg);
+
+          msg = (SSrvMsg*)transQueueGet(&conn->srvMsgs, 0);
+          if (msg != NULL) {
+            uvStartSendRespInternal(msg);
+          }
         } else {
           uvStartSendRespInternal(msg);
         }
@@ -321,6 +327,7 @@ static void uvPrepareSendData(SSrvMsg* smsg, uv_buf_t* wb) {
     pMsg->contLen = 0;
   }
   STransMsgHead* pHead = transHeadFromCont(pMsg->pCont);
+  pHead->ahandle = (uint64_t)pMsg->ahandle;
 
   // pHead->secured = pMsg->code == 0 ? 1 : 0;  //
   if (!pConn->secured) {
@@ -553,7 +560,7 @@ static bool addHandleToWorkloop(void* arg) {
   // conn set
   QUEUE_INIT(&pThrd->conn);
 
-  pThrd->asyncPool = transCreateAsyncPool(pThrd->loop, 4, pThrd, uvWorkerAsyncCb);
+  pThrd->asyncPool = transCreateAsyncPool(pThrd->loop, 5, pThrd, uvWorkerAsyncCb);
   uv_read_start((uv_stream_t*)pThrd->pipe, uvAllocConnBufferCb, uvOnConnectionCb);
   return true;
 }
@@ -617,8 +624,6 @@ static void destroyConn(SSrvConn* conn, bool clear) {
     return;
   }
   transDestroyBuffer(&conn->readBuf);
-
-  transQueueDestroy(&conn->srvMsgs);
   if (clear) {
     tTrace("server conn %p to be destroyed", conn);
     uv_shutdown_t* req = taosMemoryMalloc(sizeof(uv_shutdown_t));
@@ -634,11 +639,13 @@ static void uvDestroyConn(uv_handle_t* handle) {
 
   tDebug("server conn %p destroy", conn);
   uv_timer_stop(&conn->pTimer);
+  transQueueDestroy(&conn->srvMsgs);
   QUEUE_REMOVE(&conn->queue);
   taosMemoryFree(conn->pTcp);
   // taosMemoryFree(conn);
 
   if (thrd->quit && QUEUE_IS_EMPTY(&thrd->conn)) {
+    tTrace("work thread quit");
     uv_loop_close(thrd->loop);
     uv_stop(thrd->loop);
   }
@@ -700,12 +707,12 @@ End:
   return NULL;
 }
 void uvHandleQuit(SSrvMsg* msg, SWorkThrdObj* thrd) {
+  thrd->quit = true;
   if (QUEUE_IS_EMPTY(&thrd->conn)) {
     uv_loop_close(thrd->loop);
     uv_stop(thrd->loop);
   } else {
     destroyAllConn(thrd);
-    thrd->quit = true;
   }
   taosMemoryFree(msg);
 }
@@ -725,7 +732,7 @@ void uvHandleRelease(SSrvMsg* msg, SWorkThrdObj* thrd) {
 }
 void uvHandleResp(SSrvMsg* msg, SWorkThrdObj* thrd) {
   // send msg to client
-  tDebug("server conn %p start to send resp", msg->pConn);
+  tDebug("server conn %p start to send resp (2/2)", msg->pConn);
   uvStartSendResp(msg);
 }
 void uvHandleRegister(SSrvMsg* msg, SWorkThrdObj* thrd) {
@@ -735,9 +742,11 @@ void uvHandleRegister(SSrvMsg* msg, SWorkThrdObj* thrd) {
     if (!transQueuePush(&conn->srvMsgs, msg)) {
       return;
     }
+    transQueuePop(&conn->srvMsgs);
     conn->regArg.notifyCount = 0;
     conn->regArg.init = 1;
     conn->regArg.msg = msg->msg;
+    tDebug("server conn %p register brokenlink callback succ", conn);
 
     if (conn->broken) {
       STrans* pTransInst = conn->pTransInst;
@@ -766,15 +775,16 @@ void sendQuitToWorkThrd(SWorkThrdObj* pThrd) {
 void transCloseServer(void* arg) {
   // impl later
   SServerObj* srv = arg;
-  for (int i = 0; i < srv->numOfThreads; i++) {
-    sendQuitToWorkThrd(srv->pThreadObj[i]);
-    destroyWorkThrd(srv->pThreadObj[i]);
-  }
 
   tDebug("send quit msg to accept thread");
   uv_async_send(srv->pAcceptAsync);
   taosThreadJoin(srv->thread, NULL);
 
+  for (int i = 0; i < srv->numOfThreads; i++) {
+    sendQuitToWorkThrd(srv->pThreadObj[i]);
+    destroyWorkThrd(srv->pThreadObj[i]);
+  }
+
   taosMemoryFree(srv->pThreadObj);
   taosMemoryFree(srv->pAcceptAsync);
   taosMemoryFree(srv->loop);
@@ -815,7 +825,7 @@ void transReleaseSrvHandle(void* handle) {
   SSrvConn*     pConn = handle;
   SWorkThrdObj* pThrd = pConn->hostThrd;
 
-  STransMsg tmsg = {.handle = handle, .code = 0};
+  STransMsg tmsg = {.code = 0, .handle = handle, .ahandle = NULL};
 
   SSrvMsg* srvMsg = taosMemoryCalloc(1, sizeof(SSrvMsg));
   srvMsg->msg = tmsg;
@@ -831,12 +841,15 @@ void transSendResponse(const STransMsg* pMsg) {
   }
   SSrvConn*     pConn = pMsg->handle;
   SWorkThrdObj* pThrd = pConn->hostThrd;
+  if (pThrd->quit) {
+    return;
+  }
 
   SSrvMsg* srvMsg = taosMemoryCalloc(1, sizeof(SSrvMsg));
   srvMsg->pConn = pConn;
   srvMsg->msg = *pMsg;
   srvMsg->type = Normal;
-  tTrace("server conn %p start to send resp", pConn);
+  tTrace("server conn %p start to send resp (1/2)", pConn);
   transSendAsync(pThrd->asyncPool, &srvMsg->q);
 }
 void transRegisterMsg(const STransMsg* msg) {
diff --git a/source/libs/transport/test/transUT.cpp b/source/libs/transport/test/transUT.cpp
index 1c59879f40..9dbebd6cfe 100644
--- a/source/libs/transport/test/transUT.cpp
+++ b/source/libs/transport/test/transUT.cpp
@@ -367,9 +367,10 @@ TEST_F(TransEnv, srvReleaseHandle) {
   SRpcMsg resp = {0};
   tr->SetSrvContinueSend(processReleaseHandleCb);
   // tr->Restart(processReleaseHandleCb);
-  void *handle = NULL;
+  void *  handle = NULL;
+  SRpcMsg req = {0};
   for (int i = 0; i < 1; i++) {
-    SRpcMsg req = {0};
+    memset(&req, 0, sizeof(req));
     req.handle = resp.handle;
     req.persistHandle = 1;
     req.msgType = 1;
@@ -383,8 +384,9 @@ TEST_F(TransEnv, srvReleaseHandle) {
 }
 TEST_F(TransEnv, cliReleaseHandleExcept) {
   SRpcMsg resp = {0};
+  SRpcMsg req = {0};
   for (int i = 0; i < 3; i++) {
-    SRpcMsg req = {0};
+    memset(&req, 0, sizeof(req));
     req.handle = resp.handle;
     req.persistHandle = 1;
     req.msgType = 1;
@@ -403,8 +405,10 @@ TEST_F(TransEnv, cliReleaseHandleExcept) {
 }
 TEST_F(TransEnv, srvContinueSend) {
   tr->SetSrvContinueSend(processContinueSend);
+  SRpcMsg req = {0}, resp = {0};
   for (int i = 0; i < 10; i++) {
-    SRpcMsg req = {0}, resp = {0};
+    memset(&req, 0, sizeof(req));
+    memset(&resp, 0, sizeof(resp));
     req.msgType = 1;
     req.pCont = rpcMallocCont(10);
     req.contLen = 10;
@@ -417,8 +421,9 @@ TEST_F(TransEnv, srvPersistHandleExcept) {
   tr->SetSrvContinueSend(processContinueSend);
   // tr->SetCliPersistFp(cliPersistHandle);
   SRpcMsg resp = {0};
+  SRpcMsg req = {0};
   for (int i = 0; i < 5; i++) {
-    SRpcMsg req = {0};
+    memset(&req, 0, sizeof(req));
     req.handle = resp.handle;
     req.msgType = 1;
     req.pCont = rpcMallocCont(10);
@@ -436,8 +441,9 @@ TEST_F(TransEnv, srvPersistHandleExcept) {
 TEST_F(TransEnv, cliPersistHandleExcept) {
   tr->SetSrvContinueSend(processContinueSend);
   SRpcMsg resp = {0};
+  SRpcMsg req = {0};
   for (int i = 0; i < 5; i++) {
-    SRpcMsg req = {0};
+    memset(&req, 0, sizeof(req));
     req.handle = resp.handle;
     req.msgType = 1;
     req.pCont = rpcMallocCont(10);
@@ -459,8 +465,9 @@ TEST_F(TransEnv, multiCliPersistHandleExcept) {
 TEST_F(TransEnv, queryExcept) {
   tr->SetSrvContinueSend(processRegisterFailure);
   SRpcMsg resp = {0};
+  SRpcMsg req = {0};
   for (int i = 0; i < 5; i++) {
-    SRpcMsg req = {0};
+    memset(&req, 0, sizeof(req));
     req.handle = resp.handle;
     req.persistHandle = 1;
     req.msgType = 1;
@@ -477,8 +484,9 @@ TEST_F(TransEnv, queryExcept) {
 }
 TEST_F(TransEnv, noResp) {
   SRpcMsg resp = {0};
+  SRpcMsg req = {0};
   for (int i = 0; i < 5; i++) {
-    SRpcMsg req = {0};
+    memset(&req, 0, sizeof(req));
     req.noResp = 1;
     req.msgType = 1;
     req.pCont = rpcMallocCont(10);
diff --git a/source/libs/transport/test/transportTests.cpp b/source/libs/transport/test/transportTests.cpp
index 90122eadd1..4165e6d8c9 100644
--- a/source/libs/transport/test/transportTests.cpp
+++ b/source/libs/transport/test/transportTests.cpp
@@ -156,17 +156,15 @@ TEST_F(TransCtxEnv, mergeTest) {
     STransCtx *src = (STransCtx *)taosMemoryCalloc(1, sizeof(STransCtx));
     transCtxInit(src);
     {
-      STransCtxVal val1 = {.val = NULL, .len = 0, .freeFunc = taosMemoryFree};
+      STransCtxVal val1 = {.val = NULL, .freeFunc = taosMemoryFree};
       val1.val = taosMemoryMalloc(12);
-      val1.len = 12;
 
       taosHashPut(src->args, &key, sizeof(key), &val1, sizeof(val1));
       key++;
     }
     {
-      STransCtxVal val1 = {.val = NULL, .len = 0, .freeFunc = taosMemoryFree};
+      STransCtxVal val1 = {.val = NULL, .freeFunc = taosMemoryFree};
       val1.val = taosMemoryMalloc(12);
-      val1.len = 12;
       taosHashPut(src->args, &key, sizeof(key), &val1, sizeof(val1));
       key++;
     }
@@ -178,17 +176,15 @@ TEST_F(TransCtxEnv, mergeTest) {
     STransCtx *src = (STransCtx *)taosMemoryCalloc(1, sizeof(STransCtx));
     transCtxInit(src);
     {
-      STransCtxVal val1 = {.val = NULL, .len = 0, .freeFunc = taosMemoryFree};
+      STransCtxVal val1 = {.val = NULL, .freeFunc = taosMemoryFree};
       val1.val = taosMemoryMalloc(12);
-      val1.len = 12;
 
       taosHashPut(src->args, &key, sizeof(key), &val1, sizeof(val1));
       key++;
     }
     {
-      STransCtxVal val1 = {.val = NULL, .len = 0, .freeFunc = taosMemoryFree};
+      STransCtxVal val1 = {.val = NULL, .freeFunc = taosMemoryFree};
       val1.val = taosMemoryMalloc(12);
-      val1.len = 12;
       taosHashPut(src->args, &key, sizeof(key), &val1, sizeof(val1));
       key++;
     }
@@ -202,19 +198,17 @@ TEST_F(TransCtxEnv, mergeTest) {
     STransCtx *src = (STransCtx *)taosMemoryCalloc(1, sizeof(STransCtx));
     transCtxInit(src);
     {
-      STransCtxVal val1 = {.val = NULL, .len = 0, .freeFunc = taosMemoryFree};
+      STransCtxVal val1 = {.val = NULL, .freeFunc = taosMemoryFree};
       val1.val = taosMemoryCalloc(1, 11);
       memcpy(val1.val, val.c_str(), val.size());
-      val1.len = 11;
 
       taosHashPut(src->args, &key, sizeof(key), &val1, sizeof(val1));
       key++;
     }
     {
-      STransCtxVal val1 = {.val = NULL, .len = 0, .freeFunc = taosMemoryFree};
+      STransCtxVal val1 = {.val = NULL, .freeFunc = taosMemoryFree};
       val1.val = taosMemoryCalloc(1, 11);
       memcpy(val1.val, val.c_str(), val.size());
-      val1.len = 11;
       taosHashPut(src->args, &key, sizeof(key), &val1, sizeof(val1));
       key++;
     }
diff --git a/tests/script/tsim/db/basic1.sim b/tests/script/tsim/db/basic1.sim
index 7877bfc3a7..c07ebd0400 100644
--- a/tests/script/tsim/db/basic1.sim
+++ b/tests/script/tsim/db/basic1.sim
@@ -39,11 +39,10 @@ endi
 
 print =============== drop database
 sql drop database d1
-# todo release
-#sql show databases
-#if $rows != 1 then 
-#  return -1
-#endi
+sql show databases
+if $rows != 1 then 
+  return -1
+endi
 
 print =============== more databases
 sql create database d2 vgroups 2
diff --git a/tests/script/tsim/db/basic6.sim b/tests/script/tsim/db/basic6.sim
index 48b3fccd47..7e57fe8f1b 100644
--- a/tests/script/tsim/db/basic6.sim
+++ b/tests/script/tsim/db/basic6.sim
@@ -58,11 +58,10 @@ endi
 
 print =============== step3
 sql drop database $db
-# todo release
-#sql show databases
-#if $rows != 1 then 
-#  return -1
-#endi 
+sql show databases
+if $rows != 1 then 
+  return -1
+endi 
 
 print =============== step4
 sql_error drop database $db
@@ -319,4 +318,4 @@ if $rows != 0 then
   return -1
 endi
 
-system sh/exec.sh -n dnode1 -s stop -x SIGINT
\ No newline at end of file
+system sh/exec.sh -n dnode1 -s stop -x SIGINT
diff --git a/tests/script/tsim/db/error1.sim b/tests/script/tsim/db/error1.sim
index 09f0149a5b..6f62228ae7 100644
--- a/tests/script/tsim/db/error1.sim
+++ b/tests/script/tsim/db/error1.sim
@@ -16,17 +16,11 @@ create1:
 		return -1
 	endi
 
-# todo remove
-sql create database useless_db
-
 sql show dnodes
 if $data4_2 != ready then
 	goto create1
 endi
 
-# todo remove
-sql drop database useless_db
-
 print ========== stop dnode2
 system sh/exec.sh -n dnode2 -s stop -x SIGKILL
 
@@ -67,6 +61,7 @@ endi
 print ========== stop dnode2
 system sh/exec.sh -n dnode2 -s stop -x SIGKILL
 
+sleep 1000
 print =============== create database
 sql_error drop database d1
 
@@ -103,4 +98,4 @@ if $data03 != 0 then
 endi
 
 system sh/exec.sh -n dnode1 -s stop -x SIGINT
-system sh/exec.sh -n dnode2 -s stop -x SIGINT
\ No newline at end of file
+system sh/exec.sh -n dnode2 -s stop -x SIGINT
diff --git a/tests/script/tsim/dnode/basic1.sim b/tests/script/tsim/dnode/basic1.sim
index c5b83aa3a3..6f0d5f88b8 100644
--- a/tests/script/tsim/dnode/basic1.sim
+++ b/tests/script/tsim/dnode/basic1.sim
@@ -5,9 +5,6 @@ system sh/exec.sh -n dnode1 -s start
 system sh/exec.sh -n dnode2 -s start
 sql connect
 
-# todo remove
-sql create database useless_db
-
 print =============== show dnodes
 sql show dnodes;
 if $rows != 1 then 
@@ -83,9 +80,6 @@ if $data02 != master then
   return -1
 endi
 
-# todo remove
-sql drop database useless_db
-
 print =============== create database
 sql create database d1 vgroups 4;
 sql create database d2;
@@ -202,4 +196,4 @@ if $data00 != 1 then
 endi
 
 system sh/exec.sh -n dnode1 -s stop -x SIGINT
-system sh/exec.sh -n dnode2 -s stop -x SIGINT
\ No newline at end of file
+system sh/exec.sh -n dnode2 -s stop -x SIGINT
diff --git a/tests/script/tsim/tmq/basic.sim b/tests/script/tsim/tmq/basic.sim
index 3e42c2cbd7..876cf7e266 100644
--- a/tests/script/tsim/tmq/basic.sim
+++ b/tests/script/tsim/tmq/basic.sim
@@ -6,9 +6,6 @@ system sh/exec.sh -n dnode1 -s start
 sleep 500
 sql connect
 
-# todo remove
-sql create database useless_db
-
 $loop_cnt = 0
 check_dnode_ready:
 	$loop_cnt = $loop_cnt + 1
@@ -26,9 +23,6 @@ if $data04 != ready then
   goto check_dnode_ready
 endi
 
-# todo remove
-sql drop database useless_db
-
 #root@trd02 /data2/dnode $ tmq_demo --help                                                                          
 #Used to tmq_demo                                                                   
 #        -c      Configuration directory, default is                                                                
diff --git a/tests/script/tsim/user/basic1.sim b/tests/script/tsim/user/basic1.sim
index e14aa3af2f..7af5ba8d00 100644
--- a/tests/script/tsim/user/basic1.sim
+++ b/tests/script/tsim/user/basic1.sim
@@ -3,9 +3,6 @@ system sh/deploy.sh -n dnode1 -i 1
 system sh/exec.sh -n dnode1 -s start
 sql connect
 
-# todo remove
-sql create database useless_db
-
 print =============== show users
 sql show users
 if $rows != 1 then 
@@ -74,7 +71,4 @@ print $data10 $data11 $data22
 print $data20 $data11 $data22
 print $data30 $data31 $data32
 
-# todo remove
-sql drop database useless_db
-
-system sh/exec.sh -n dnode1 -s stop -x SIGINT
\ No newline at end of file
+system sh/exec.sh -n dnode1 -s stop -x SIGINT
diff --git a/tools/shell/src/shellEngine.c b/tools/shell/src/shellEngine.c
index 0de663f279..47d47f023d 100644
--- a/tools/shell/src/shellEngine.c
+++ b/tools/shell/src/shellEngine.c
@@ -358,6 +358,7 @@ void shellRunCommandOnServer(TAOS *con, char command[]) {
     } else {
       printf("Query interrupted (%s), %d row(s) in set (%.6fs)\n", taos_errstr(pSql), numOfRows, (et - st) / 1E6);
     }
+    taos_free_result(pSql);    
   } else {
     int num_rows_affacted = taos_affected_rows(pSql);
     taos_free_result(pSql);