diff --git a/src/dnode/src/dnodeMgmt.c b/src/dnode/src/dnodeMgmt.c
index cf1de5eab9574cfbebb5810349c479afe697c079..4d335d73534b452b71753b63d6d1b814b0df674b 100644
--- a/src/dnode/src/dnodeMgmt.c
+++ b/src/dnode/src/dnodeMgmt.c
@@ -225,17 +225,17 @@ static int32_t dnodeOpenVnode(int32_t vnode, char *rootDir) {
   vnodeObj.status   = TSDB_VN_STATUS_NOT_READY;
   vnodeObj.refCount = 1;
   vnodeObj.version  = 0;
-  vnodeObj.wworker  = dnodeAllocateWriteWorker();
-  vnodeObj.rworker  = dnodeAllocateReadWorker();
   vnodeObj.wal      = NULL;
   vnodeObj.tsdb     = pTsdb;
   vnodeObj.replica  = NULL;
   vnodeObj.events   = NULL;
   vnodeObj.cq       = NULL;
 
-  taosAddIntHash(tsDnodeVnodesHash, vnodeObj.vgId, (char *) (&vnodeObj));
+  SVnodeObj *pVnode = (SVnodeObj *)taosAddIntHash(tsDnodeVnodesHash, vnodeObj.vgId, (char *)(&vnodeObj));
+  pVnode->wworker = dnodeAllocateWriteWorker(pVnode);
+  pVnode->rworker = dnodeAllocateReadWorker(pVnode);
 
-  dTrace("open vnode:%d in %s", vnodeObj.vgId, rootDir);
+  dTrace("open vnode:%d in %s", pVnode->vgId, rootDir);
   return TSDB_CODE_SUCCESS;
 }
 
@@ -314,17 +314,17 @@ static int32_t dnodeCreateVnode(SMDCreateVnodeMsg *pVnodeCfg) {
   vnodeObj.status   = TSDB_VN_STATUS_NOT_READY;
   vnodeObj.refCount = 1;
   vnodeObj.version  = 0;
-  vnodeObj.wworker  = dnodeAllocateWriteWorker();
-  vnodeObj.rworker  = dnodeAllocateReadWorker();
   vnodeObj.wal      = NULL;
   vnodeObj.tsdb     = pTsdb;
   vnodeObj.replica  = NULL;
   vnodeObj.events   = NULL;
   vnodeObj.cq       = NULL;
 
-  taosAddIntHash(tsDnodeVnodesHash, vnodeObj.vgId, (char *) (&vnodeObj));
+  SVnodeObj *pVnode = (SVnodeObj *)taosAddIntHash(tsDnodeVnodesHash, vnodeObj.vgId, (char *)(&vnodeObj));
+  pVnode->wworker = dnodeAllocateWriteWorker(pVnode);
+  pVnode->rworker = dnodeAllocateReadWorker(pVnode);
 
-  dPrint("vgroup:%d, vnode:%d is created", vnodeObj.vgId, vnodeObj.vgId);
+  dPrint("vgroup:%d, vnode:%d is created", pVnode->vgId, pVnode->vgId);
   return TSDB_CODE_SUCCESS;
 }
 
diff --git a/src/dnode/src/dnodeRead.c b/src/dnode/src/dnodeRead.c
index 3419128c72647c5a88dd62ab1ff51f80f407e26c..d6ecf2fa66b0cf4cbaaa4cbcd061d6ff13d6c4a9 100644
--- a/src/dnode/src/dnodeRead.c
+++ b/src/dnode/src/dnodeRead.c
@@ -36,16 +36,15 @@ typedef struct {
   void        *pCont;
   int32_t      contLen;
   SRpcMsg      rpcMsg;
-  void        *pVnode;
   SRpcContext *pRpcContext;  // RPC message context
 } SReadMsg;
 
 static void *dnodeProcessReadQueue(void *param);
-static void  dnodeProcessReadResult(SReadMsg *pRead);
+static void  dnodeProcessReadResult(void *pVnode, SReadMsg *pRead);
 static void  dnodeHandleIdleReadWorker();
-static void  dnodeProcessQueryMsg(SReadMsg *pMsg);
-static void  dnodeProcessRetrieveMsg(SReadMsg *pMsg);
-static void(*dnodeProcessReadMsgFp[TSDB_MSG_TYPE_MAX])(SReadMsg *pNode);
+static void  dnodeProcessQueryMsg(void *pVnode, SReadMsg *pMsg);
+static void  dnodeProcessRetrieveMsg(void *pVnode, SReadMsg *pMsg);
+static void(*dnodeProcessReadMsgFp[TSDB_MSG_TYPE_MAX])(void *pVnode, SReadMsg *pNode);
 
 // module global variable
 static taos_qset readQset;
@@ -104,23 +103,19 @@ void dnodeRead(SRpcMsg *pMsg) {
     }
 
     // put message into queue
-    SReadMsg readMsg = {
-      .rpcMsg      = *pMsg,
-      .pCont       = pCont,
-      .contLen     = pHead->contLen,
-      .pRpcContext = pRpcContext,
-      .pVnode      = pVnode,
-    };
+    SReadMsg *pRead = (SReadMsg *)taosAllocateQitem(sizeof(SReadMsg));
+    pRead->rpcMsg      = *pMsg;
+    pRead->pCont       = pCont;
+    pRead->contLen     = pHead->contLen;
+    pRead->pRpcContext = pRpcContext;
 
     taos_queue queue = dnodeGetVnodeRworker(pVnode);
-    taosWriteQitem(queue, &readMsg);
+    taosWriteQitem(queue, TAOS_QTYPE_RPC, pRead);
 
     // next vnode
     leftLen -= pHead->contLen;
     pCont -= pHead->contLen;
     queuedMsgNum++;
-
-    dnodeReleaseVnode(pVnode);
   }
 
   if (queuedMsgNum == 0) {
@@ -135,11 +130,11 @@ void dnodeRead(SRpcMsg *pMsg) {
   }
 }
 
-void *dnodeAllocateReadWorker() {
+void *dnodeAllocateReadWorker(void *pVnode) {
   taos_queue *queue = taosOpenQueue(sizeof(SReadMsg));
   if (queue == NULL) return NULL;
 
-  taosAddIntoQset(readQset, queue);
+  taosAddIntoQset(readQset, queue, pVnode);
 
   // spawn a thread to process queue
   if (threads < maxThreads) {
@@ -164,20 +159,27 @@ void dnodeFreeReadWorker(void *rqueue) {
 
 static void *dnodeProcessReadQueue(void *param) {
   taos_qset  qset = (taos_qset)param;
-  SReadMsg   readMsg;
+  SReadMsg  *pReadMsg;
+  int        type;
+  void      *pVnode;
 
   while (1) {
-    if (taosReadQitemFromQset(qset, &readMsg) <= 0) {
+    if (taosReadQitemFromQset(qset, &type, (void **)&pReadMsg, (void **)&pVnode) == 0) {
       dnodeHandleIdleReadWorker();
       continue;
     }
 
     terrno = 0;
-    if (dnodeProcessReadMsgFp[readMsg.rpcMsg.msgType]) {
-      (*dnodeProcessReadMsgFp[readMsg.rpcMsg.msgType]) (&readMsg);
+    if (dnodeProcessReadMsgFp[pReadMsg->rpcMsg.msgType]) {
+      (*dnodeProcessReadMsgFp[pReadMsg->rpcMsg.msgType]) (pVnode, pReadMsg);
     } else {
       terrno = TSDB_CODE_MSG_NOT_PROCESSED;
     }
+
+    dnodeProcessReadResult(pVnode, pReadMsg);
+    taosFreeQitem(pReadMsg);
+
+    dnodeReleaseVnode(pVnode);  
   }
 
   return NULL;
@@ -195,11 +197,11 @@ static void dnodeHandleIdleReadWorker() {
   }
 }
 
-static void dnodeProcessReadResult(SReadMsg *pRead) {
+static void dnodeProcessReadResult(void *pVnode, SReadMsg *pRead) {
   SRpcContext *pRpcContext = pRead->pRpcContext;
   int32_t      code = 0;
 
-  dnodeReleaseVnode(pRead->pVnode);
+  dnodeReleaseVnode(pVnode);
 
   if (pRpcContext) {
     if (terrno) {
@@ -218,19 +220,23 @@ static void dnodeProcessReadResult(SReadMsg *pRead) {
     code = terrno;
   }
 
-  SRpcMsg rsp;
-  rsp.handle = pRead->rpcMsg.handle;
-  rsp.code   = code;
-  rsp.pCont  = NULL;
-  rpcSendResponse(&rsp);
+  //TODO: query handle is returned by dnodeProcessQueryMsg 
+  if (0) {
+    SRpcMsg rsp;
+    rsp.handle = pRead->rpcMsg.handle;
+    rsp.code   = code;
+    rsp.pCont  = NULL;
+    rpcSendResponse(&rsp);
+  }
+  
   rpcFreeCont(pRead->rpcMsg.pCont);  // free the received message
 }
 
-static void dnodeProcessQueryMsg(SReadMsg *pMsg) {
+static void dnodeProcessQueryMsg(void *pVnode, SReadMsg *pMsg) {
   SQueryTableMsg* pQueryTableMsg = (SQueryTableMsg*) pMsg->pCont;
   
   SQInfo* pQInfo = NULL;
-  void* tsdb = dnodeGetVnodeTsdb(pMsg->pVnode);
+  void* tsdb = dnodeGetVnodeTsdb(pVnode);
   int32_t code = qCreateQueryInfo(tsdb, pQueryTableMsg, &pQInfo);
   
   SQueryTableRsp *pRsp = (SQueryTableRsp *) rpcMallocCont(sizeof(SQueryTableRsp));
@@ -252,7 +258,7 @@ static void dnodeProcessQueryMsg(SReadMsg *pMsg) {
 }
 
 static int32_t c = 0;
-static void dnodeProcessRetrieveMsg(SReadMsg *pMsg) {
+static void dnodeProcessRetrieveMsg(void *pVnode, SReadMsg *pMsg) {
   SRetrieveTableMsg *pRetrieve = pMsg->pCont;
   void *pQInfo = (void*) htobe64(pRetrieve->qhandle);
 
diff --git a/src/dnode/src/dnodeWrite.c b/src/dnode/src/dnodeWrite.c
index eb9c42a93fa02cc38b53c55e0fa3e5b6b257d500..7ec206f366a3e1b7151a6dae043dbc7937eb2a35 100644
--- a/src/dnode/src/dnodeWrite.c
+++ b/src/dnode/src/dnodeWrite.c
@@ -35,7 +35,6 @@ typedef struct _write {
   void        *pCont;
   int32_t      contLen;
   SRpcMsg      rpcMsg;
-  void        *pVnode;      // pointer to vnode
   SRpcContext *pRpcContext; // RPC message context
 } SWriteMsg;
 
@@ -51,15 +50,15 @@ typedef struct _thread_obj {
   SWriteWorker  *writeWorker;
 } SWriteWorkerPool;
 
-static void (*dnodeProcessWriteMsgFp[TSDB_MSG_TYPE_MAX])(SWriteMsg *);
+static void (*dnodeProcessWriteMsgFp[TSDB_MSG_TYPE_MAX])(void *, SWriteMsg *);
 static void  *dnodeProcessWriteQueue(void *param);
 static void   dnodeHandleIdleWorker(SWriteWorker *pWorker);
-static void   dnodeProcessWriteResult(SWriteMsg *pWrite);
-static void   dnodeProcessSubmitMsg(SWriteMsg *pMsg);
-static void   dnodeProcessCreateTableMsg(SWriteMsg *pMsg);
-static void   dnodeProcessDropTableMsg(SWriteMsg *pMsg);
-static void   dnodeProcessAlterTableMsg(SWriteMsg *pMsg);
-static void   dnodeProcessDropStableMsg(SWriteMsg *pMsg);
+static void   dnodeProcessWriteResult(void *pVnode, SWriteMsg *pWrite);
+static void   dnodeProcessSubmitMsg(void *pVnode, SWriteMsg *pMsg);
+static void   dnodeProcessCreateTableMsg(void *pVnode, SWriteMsg *pMsg);
+static void   dnodeProcessDropTableMsg(void *pVnode, SWriteMsg *pMsg);
+static void   dnodeProcessAlterTableMsg(void *pVnode, SWriteMsg *pMsg);
+static void   dnodeProcessDropStableMsg(void *pVnode, SWriteMsg *pMsg);
 
 SWriteWorkerPool wWorkerPool;
 
@@ -116,15 +115,14 @@ void dnodeWrite(SRpcMsg *pMsg) {
     }
    
     // put message into queue
-    SWriteMsg writeMsg;
-    writeMsg.rpcMsg      = *pMsg;
-    writeMsg.pCont       = pCont;
-    writeMsg.contLen     = pHead->contLen;
-    writeMsg.pRpcContext = pRpcContext;
-    writeMsg.pVnode      = pVnode;  // pVnode shall be saved for usage later
+    SWriteMsg *pWrite = (SWriteMsg *)taosAllocateQitem(sizeof(SWriteMsg));
+    pWrite->rpcMsg      = *pMsg;
+    pWrite->pCont       = pCont;
+    pWrite->contLen     = pHead->contLen;
+    pWrite->pRpcContext = pRpcContext;
  
     taos_queue queue = dnodeGetVnodeWworker(pVnode);
-    taosWriteQitem(queue, &writeMsg);
+    taosWriteQitem(queue, TAOS_QTYPE_RPC, pWrite);
 
     // next vnode 
     leftLen -= pHead->contLen;
@@ -144,16 +142,16 @@ void dnodeWrite(SRpcMsg *pMsg) {
   }
 }
 
-void *dnodeAllocateWriteWorker() {
+void *dnodeAllocateWriteWorker(void *pVnode) {
   SWriteWorker *pWorker = wWorkerPool.writeWorker + wWorkerPool.nextId;
-  taos_queue *queue = taosOpenQueue(sizeof(SWriteMsg));
+  taos_queue *queue = taosOpenQueue();
   if (queue == NULL) return NULL;
 
   if (pWorker->qset == NULL) {
     pWorker->qset = taosOpenQset();
     if (pWorker->qset == NULL) return NULL;
 
-    taosAddIntoQset(pWorker->qset, queue);
+    taosAddIntoQset(pWorker->qset, queue, pVnode);
     wWorkerPool.nextId = (wWorkerPool.nextId + 1) % wWorkerPool.max;
 
     pthread_attr_t thAttr;
@@ -165,7 +163,7 @@ void *dnodeAllocateWriteWorker() {
       taosCloseQset(pWorker->qset);
     }
   } else {
-    taosAddIntoQset(pWorker->qset, queue);
+    taosAddIntoQset(pWorker->qset, queue, pVnode);
     wWorkerPool.nextId = (wWorkerPool.nextId + 1) % wWorkerPool.max;
   }
 
@@ -181,53 +179,57 @@ void dnodeFreeWriteWorker(void *wqueue) {
 static void *dnodeProcessWriteQueue(void *param) {
   SWriteWorker *pWorker = (SWriteWorker *)param;
   taos_qall     qall;
-  SWriteMsg     writeMsg;
+  SWriteMsg    *pWriteMsg;
   int32_t       numOfMsgs;
+  int           type;
+  void         *pVnode;
+
+  qall = taosAllocateQall();
 
   while (1) {
-    numOfMsgs = taosReadAllQitemsFromQset(pWorker->qset, &qall);
+    numOfMsgs = taosReadAllQitemsFromQset(pWorker->qset, qall, &pVnode);
     if (numOfMsgs <=0) { 
       dnodeHandleIdleWorker(pWorker);  // thread exit if no queues anymore
       continue;
     }
 
-    for (int32_t i=0; i<numOfMsgs; ++i) {
+    for (int32_t i = 0; i < numOfMsgs; ++i) {
       // retrieve all items, and write them into WAL
-      taosGetQitem(qall, &writeMsg);
+      taosGetQitem(qall, &type, (void **)&pWriteMsg);
 
       // walWrite(pVnode->whandle, writeMsg.rpcMsg.msgType, writeMsg.pCont, writeMsg.contLen);
     }
-    
+
     // flush WAL file
     // walFsync(pVnode->whandle);
 
     // browse all items, and process them one by one
     taosResetQitems(qall);
     for (int32_t i = 0; i < numOfMsgs; ++i) {
-      taosGetQitem(qall, &writeMsg);
+      taosGetQitem(qall, &type, (void **)&pWriteMsg);
 
       terrno = 0;
-      if (dnodeProcessWriteMsgFp[writeMsg.rpcMsg.msgType]) {
-        (*dnodeProcessWriteMsgFp[writeMsg.rpcMsg.msgType]) (&writeMsg);
+      if (dnodeProcessWriteMsgFp[pWriteMsg->rpcMsg.msgType]) {
+        (*dnodeProcessWriteMsgFp[pWriteMsg->rpcMsg.msgType]) (pVnode, pWriteMsg);
       } else {
         terrno = TSDB_CODE_MSG_NOT_PROCESSED;  
       }
      
-      dnodeProcessWriteResult(&writeMsg);
+      dnodeProcessWriteResult(pVnode, pWriteMsg);
+      taosFreeQitem(pWriteMsg);
     }
-
-    // free the Qitems;
-    taosFreeQitems(qall);
   }
 
+  taosFreeQall(qall);
+
   return NULL;
 }
 
-static void dnodeProcessWriteResult(SWriteMsg *pWrite) {
+static void dnodeProcessWriteResult(void *pVnode, SWriteMsg *pWrite) {
   SRpcContext *pRpcContext = pWrite->pRpcContext;
   int32_t      code = 0;
 
-  dnodeReleaseVnode(pWrite->pVnode);
+  dnodeReleaseVnode(pVnode);
 
   if (pRpcContext) {
     if (terrno) {
@@ -267,7 +269,7 @@ static void dnodeHandleIdleWorker(SWriteWorker *pWorker) {
   }
 }
 
-static void dnodeProcessSubmitMsg(SWriteMsg *pMsg) {
+static void dnodeProcessSubmitMsg(void *pVnode, SWriteMsg *pMsg) {
   dTrace("submit msg is disposed");
 
   SShellSubmitRspMsg *pRsp = rpcMallocCont(sizeof(SShellSubmitRspMsg));
@@ -276,7 +278,7 @@ static void dnodeProcessSubmitMsg(SWriteMsg *pMsg) {
   pRsp->affectedRows      = htonl(1);
   pRsp->numOfFailedBlocks = 0;
   
-  void* tsdb = dnodeGetVnodeTsdb(pMsg->pVnode);
+  void* tsdb = dnodeGetVnodeTsdb(pVnode);
   assert(tsdb != NULL);
   
   tsdbInsertData(tsdb, pMsg->pCont);
@@ -292,7 +294,7 @@ static void dnodeProcessSubmitMsg(SWriteMsg *pMsg) {
   rpcSendResponse(&rpcRsp);
 }
 
-static void dnodeProcessCreateTableMsg(SWriteMsg *pMsg) {
+static void dnodeProcessCreateTableMsg(void *pVnode, SWriteMsg *pMsg) {
   SMDCreateTableMsg *pTable = pMsg->rpcMsg.pCont;
   SRpcMsg rpcRsp = {.handle = pMsg->rpcMsg.handle, .pCont = NULL, .contLen = 0, .code = 0, .msgType = 0};
 
@@ -341,16 +343,16 @@ static void dnodeProcessCreateTableMsg(SWriteMsg *pMsg) {
     tsdbTableSetTagValue(&tCfg, dataRow, false);
   }
 
-  void *pTsdb = dnodeGetVnodeTsdb(pMsg->pVnode);
+  void *pTsdb = dnodeGetVnodeTsdb(pVnode);
 
   rpcRsp.code = tsdbCreateTable(pTsdb, &tCfg);
-  dnodeReleaseVnode(pMsg->pVnode);
+  dnodeReleaseVnode(pVnode);
 
   dTrace("table:%s, create table result:%s", pTable->tableId, tstrerror(rpcRsp.code));
   rpcSendResponse(&rpcRsp);
 }
 
-static void dnodeProcessDropTableMsg(SWriteMsg *pMsg) {
+static void dnodeProcessDropTableMsg(void *pVnode, SWriteMsg *pMsg) {
   SMDDropTableMsg *pTable = pMsg->rpcMsg.pCont;
   SRpcMsg rpcRsp = {.handle = pMsg->rpcMsg.handle, .pCont = NULL, .contLen = 0, .code = 0, .msgType = 0};
 
@@ -360,16 +362,16 @@ static void dnodeProcessDropTableMsg(SWriteMsg *pMsg) {
     .tid = htonl(pTable->sid)
   };
 
-  void *pTsdb = dnodeGetVnodeTsdb(pMsg->pVnode);
+  void *pTsdb = dnodeGetVnodeTsdb(pVnode);
 
   rpcRsp.code = tsdbDropTable(pTsdb, tableId);
-  dnodeReleaseVnode(pMsg->pVnode);
+  dnodeReleaseVnode(pVnode);
 
   dTrace("table:%s, drop table result:%s", pTable->tableId, tstrerror(rpcRsp.code));
   rpcSendResponse(&rpcRsp);
 }
 
-static void dnodeProcessAlterTableMsg(SWriteMsg *pMsg) {
+static void dnodeProcessAlterTableMsg(void *pVnode, SWriteMsg *pMsg) {
   SMDCreateTableMsg *pTable = pMsg->rpcMsg.pCont;
   SRpcMsg rpcRsp = {.handle = pMsg->rpcMsg.handle, .pCont = NULL, .contLen = 0, .code = 0, .msgType = 0};
 
@@ -418,16 +420,16 @@ static void dnodeProcessAlterTableMsg(SWriteMsg *pMsg) {
     tsdbTableSetTagValue(&tCfg, dataRow, false);
   }
 
-  void *pTsdb = dnodeGetVnodeTsdb(pMsg->pVnode);
+  void *pTsdb = dnodeGetVnodeTsdb(pVnode);
 
   rpcRsp.code = tsdbAlterTable(pTsdb, &tCfg);
-  dnodeReleaseVnode(pMsg->pVnode);
+  dnodeReleaseVnode(pVnode);
 
   dTrace("table:%s, alter table result:%s", pTable->tableId, tstrerror(rpcRsp.code));
   rpcSendResponse(&rpcRsp);
 }
 
-static void dnodeProcessDropStableMsg(SWriteMsg *pMsg) {
+static void dnodeProcessDropStableMsg(void *pVnode, SWriteMsg *pMsg) {
   SMDDropSTableMsg *pTable = pMsg->rpcMsg.pCont;
   SRpcMsg rpcRsp = {.handle = pMsg->rpcMsg.handle, .pCont = NULL, .contLen = 0, .code = 0, .msgType = 0};
 
@@ -439,7 +441,7 @@ static void dnodeProcessDropStableMsg(SWriteMsg *pMsg) {
   //rpcRsp.code = tsdbDropSTable(pTsdb, pTable->uid);
 
   rpcRsp.code = TSDB_CODE_SUCCESS;
-  dnodeReleaseVnode(pMsg->pVnode);
+  dnodeReleaseVnode(pVnode);
 
   dTrace("stable:%s, drop stable result:%s", pTable->tableId, tstrerror(rpcRsp.code));
   rpcSendResponse(&rpcRsp);
diff --git a/src/inc/taosdef.h b/src/inc/taosdef.h
index 570e2e1acd0391f2f59f56b9b68b52e38310da14..d6a9447e3d192120a2712b46d1b2310c2732344f 100644
--- a/src/inc/taosdef.h
+++ b/src/inc/taosdef.h
@@ -176,7 +176,7 @@ void tsDataSwap(void *pLeft, void *pRight, int32_t type, int32_t size);
 #define TSDB_MAX_COLUMNS          256
 #define TSDB_MIN_COLUMNS          2       //PRIMARY COLUMN(timestamp) + other columns
 
-#define TSDB_DNODE_NAME_LEN       63
+#define TSDB_DNODE_NAME_LEN       64
 #define TSDB_TABLE_NAME_LEN       192
 #define TSDB_DB_NAME_LEN          32
 #define TSDB_COL_NAME_LEN         64
diff --git a/src/mnode/inc/mgmtSuperTable.h b/src/mnode/inc/mgmtSuperTable.h
index 922aafed7f9344ad908893cb6c7e6278a541bf35..6d0c565c3022f09460a4ec3eb84bc66c797030b7 100644
--- a/src/mnode/inc/mgmtSuperTable.h
+++ b/src/mnode/inc/mgmtSuperTable.h
@@ -45,7 +45,8 @@ void *  mgmtGetSuperTableVgroup(SSuperTableObj *pStable);
 int32_t mgmtFindSuperTableTagIndex(SSuperTableObj *pTable, const char *tagName);
 int32_t mgmtSetSchemaFromSuperTable(SSchema *pSchema, SSuperTableObj *pTable);
 
-void mgmtDropAllSuperTables(SDbObj *pDropDb);
+void    mgmtDropAllSuperTables(SDbObj *pDropDb);
+int32_t mgmtExtractTableName(const char* tableId, char* name);
 
 #ifdef __cplusplus
 }
diff --git a/src/mnode/src/mgmtSuperTable.c b/src/mnode/src/mgmtSuperTable.c
index f2b54ec000091914f49a5f1b94b97cffc1bed8e6..e8161deb4dc10b27277ab18e7248acf7a7b08967 100644
--- a/src/mnode/src/mgmtSuperTable.c
+++ b/src/mnode/src/mgmtSuperTable.c
@@ -524,7 +524,7 @@ int32_t mgmtRetrieveShowSuperTables(SShowObj *pShow, char *data, int32_t rows, v
     }
 
     memset(stableName, 0, tListLen(stableName));
-    extractTableName(pTable->tableId, stableName);
+    mgmtExtractTableName(pTable->tableId, stableName);
 
     if (pShow->payloadLen > 0 &&
         patternMatch(pShow->payload, stableName, TSDB_TABLE_NAME_LEN, &info) != TSDB_PATTERN_MATCH)
@@ -624,3 +624,17 @@ int32_t mgmtGetSuperTableMeta(SDbObj *pDb, SSuperTableObj *pTable, STableMetaMsg
   return TSDB_CODE_SUCCESS;
 }
 
+int32_t mgmtExtractTableName(const char* tableId, char* name) {
+  int pos = -1;
+  int num = 0;
+  for (pos = 0; tableId[pos] != 0; ++pos) {
+    if (tableId[pos] == '.') num++;
+    if (num == 2) break;
+  }
+
+  if (num == 2) {
+    strcpy(name, tableId + pos + 1);
+  }
+  return 0;
+}
+
diff --git a/src/mnode/src/mgmtTable.c b/src/mnode/src/mgmtTable.c
index 675de57924ccb46650085510079459a6c678f454..491e65979a5fc934970a6d899ac09e7dd06ceb07 100644
--- a/src/mnode/src/mgmtTable.c
+++ b/src/mnode/src/mgmtTable.c
@@ -310,7 +310,7 @@ int32_t mgmtRetrieveShowTables(SShowObj *pShow, char *data, int32_t rows, void *
     numOfRead++;
 
     // pattern compare for meter name
-    extractTableName(tableId, tableName);
+    mgmtExtractTableName(tableId, tableName);
 
     if (pShow->payloadLen > 0 &&
         patternMatch(pShow->payload, tableName, TSDB_TABLE_NAME_LEN, &info) != TSDB_PATTERN_MATCH) {
@@ -333,7 +333,7 @@ int32_t mgmtRetrieveShowTables(SShowObj *pShow, char *data, int32_t rows, void *
 
     pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
     if (superTableId != NULL) {
-      extractTableName(superTableId, pWrite);
+      mgmtExtractTableName(superTableId, pWrite);
     }
     cols++;
 
diff --git a/src/rpc/test/rserver.c b/src/rpc/test/rserver.c
index d9e5da51a67f34c7eeeff3c148e93b26defdc9c4..6c5b320809b8c714a3f30caefa952e289b57a36d 100644
--- a/src/rpc/test/rserver.c
+++ b/src/rpc/test/rserver.c
@@ -28,10 +28,13 @@ void *qhandle = NULL;
 void processShellMsg() {
   static int num = 0;
   taos_qall  qall;
-  SRpcMsg    rpcMsg;
+  SRpcMsg   *pRpcMsg, rpcMsg;
+  int        type;
+ 
+  qall = taosAllocateQall();
 
   while (1) {
-    int numOfMsgs = taosReadAllQitems(qhandle, &qall);
+    int numOfMsgs = taosReadAllQitems(qhandle, qall);
     if (numOfMsgs <= 0) {
       usleep(1000);
       continue;
@@ -40,10 +43,10 @@ void processShellMsg() {
     tTrace("%d shell msgs are received", numOfMsgs);
 
     for (int i=0; i<numOfMsgs; ++i) {
-      taosGetQitem(qall, &rpcMsg);
+      taosGetQitem(qall, &type, (void **)&pRpcMsg);
  
       if (dataFd >=0) {
-        if ( write(dataFd, rpcMsg.pCont, rpcMsg.contLen) <0 ) {
+        if ( write(dataFd, pRpcMsg->pCont, pRpcMsg->contLen) <0 ) {
           tPrint("failed to write data file, reason:%s", strerror(errno));
         }
       }
@@ -62,19 +65,22 @@ void processShellMsg() {
   
     taosResetQitems(qall);
     for (int i=0; i<numOfMsgs; ++i) {
-      taosGetQitem(qall, &rpcMsg);
 
-      rpcFreeCont(rpcMsg.pCont);
+      taosGetQitem(qall, &type, (void **)&pRpcMsg);
+      rpcFreeCont(pRpcMsg->pCont);
+
       rpcMsg.pCont = rpcMallocCont(msgSize);
       rpcMsg.contLen = msgSize;
-      rpcMsg.handle = rpcMsg.handle;
+      rpcMsg.handle = pRpcMsg->handle;
       rpcMsg.code = 1;
       rpcSendResponse(&rpcMsg);
+
+      taosFreeQitem(pRpcMsg);
     }
 
-    taosFreeQitems(qall);
   }
 
+  taosFreeQall(qall);
 /*
   SRpcIpSet ipSet;
   ipSet.numOfIps = 1;
@@ -108,8 +114,13 @@ int retrieveAuthInfo(char *meterId, char *spi, char *encrypt, char *secret, char
 }
 
 void processRequestMsg(SRpcMsg *pMsg) {
-  tTrace("request is received, type:%d, contLen:%d", pMsg->msgType, pMsg->contLen);
-  taosWriteQitem(qhandle, pMsg); 
+  SRpcMsg *pTemp;
+
+  pTemp = taosAllocateQitem(sizeof(SRpcMsg));
+  memcpy(pTemp, pMsg, sizeof(SRpcMsg));
+
+  tTrace("request is received, type:%d, contLen:%d, item:%p", pMsg->msgType, pMsg->contLen, pTemp);
+  taosWriteQitem(qhandle, TAOS_QTYPE_RPC, pTemp); 
 }
 
 int main(int argc, char *argv[]) {
@@ -143,6 +154,7 @@ int main(int argc, char *argv[]) {
       commit = atoi(argv[++i]);
     } else if (strcmp(argv[i], "-d")==0 && i < argc-1) {
       rpcDebugFlag = atoi(argv[++i]);
+      ddebugFlag = rpcDebugFlag;
       uDebugFlag = rpcDebugFlag;
     } else {
       printf("\nusage: %s [options] \n", argv[0]);
diff --git a/src/util/inc/tlog.h b/src/util/inc/tlog.h
index 3a327b0a471c4671c684d80e0215f0c863239418..8a3bd6bc7c9b2728430f5341d0f1b0c94bc9b17c 100644
--- a/src/util/inc/tlog.h
+++ b/src/util/inc/tlog.h
@@ -78,7 +78,7 @@ void taosResetLogFile();
 // utility log function
 #define pError(...)                          \
   if (uDebugFlag & DEBUG_ERROR) {            \
-    tprintf("ERROR UTL ", 255, __VA_ARGS__); \
+    tprintf("ERROR UTL ", uDebugFlag, __VA_ARGS__); \
   }
 #define pWarn(...)                                  \
   if (uDebugFlag & DEBUG_WARN) {                    \
diff --git a/src/util/inc/tqueue.h b/src/util/inc/tqueue.h
index 97408110d4d8acc9c5b77b0fe296e58c32ec8275..c45eb10518765e65142eabd3294c8cc851331f3a 100644
--- a/src/util/inc/tqueue.h
+++ b/src/util/inc/tqueue.h
@@ -20,28 +20,35 @@
 extern "C" {
 #endif
 
+#define TAOS_QTYPE_RPC      0
+#define TAOS_QTYPE_FWD      1
+#define TAOS_QTYPE_WAL      2 
+
 typedef void* taos_queue;
 typedef void* taos_qset;
 typedef void* taos_qall;
 
-taos_queue taosOpenQueue(int itemSize);
+taos_queue taosOpenQueue();
 void       taosCloseQueue(taos_queue);
-int        taosWriteQitem(taos_queue, void *item);
-int        taosReadQitem(taos_queue, void *item);
-
-int        taosReadAllQitems(taos_queue, taos_qall *);
-int        taosGetQitem(taos_qall, void *item);
+void      *taosAllocateQitem(int size);
+void       taosFreeQitem(void *item);
+int        taosWriteQitem(taos_queue, int type, void *item);
+int        taosReadQitem(taos_queue, int *type, void **pitem);
+
+taos_qall  taosAllocateQall();
+void       taosFreeQall(taos_qall);
+int        taosReadAllQitems(taos_queue, taos_qall);
+int        taosGetQitem(taos_qall, int *type, void **pitem);
 void       taosResetQitems(taos_qall);
-void       taosFreeQitems(taos_qall);
 
 taos_qset  taosOpenQset();
 void       taosCloseQset();
-int        taosAddIntoQset(taos_qset, taos_queue);
+int        taosAddIntoQset(taos_qset, taos_queue, void *ahandle);
 void       taosRemoveFromQset(taos_qset, taos_queue);
 int        taosGetQueueNumber(taos_qset);
 
-int        taosReadQitemFromQset(taos_qset, void *item);
-int        taosReadAllQitemsFromQset(taos_qset, taos_qall *);
+int        taosReadQitemFromQset(taos_qset, int *type, void **pitem, void **handle);
+int        taosReadAllQitemsFromQset(taos_qset, taos_qall, void **handle);
 
 int        taosGetQueueItemsNumber(taos_queue param);
 int        taosGetQsetItemsNumber(taos_qset param);
diff --git a/src/util/src/tqueue.c b/src/util/src/tqueue.c
index cb218126a877714c71ef2363960695fa4fb7694b..1ac05556d6a90eb664c0a907f752010bf4ff52f5 100644
--- a/src/util/src/tqueue.c
+++ b/src/util/src/tqueue.c
@@ -19,6 +19,7 @@
 #include "tqueue.h"
 
 typedef struct _taos_qnode {
+  int                 type;
   struct _taos_qnode *next;
   char                item[];
 } STaosQnode;
@@ -30,6 +31,7 @@ typedef struct _taos_q {
   struct _taos_qnode *tail;
   struct _taos_q     *next;    // for queue set
   struct _taos_qset  *qset;    // for queue set
+  void               *ahandle; // for queue set
   pthread_mutex_t     mutex;  
 } STaosQueue;
 
@@ -48,7 +50,7 @@ typedef struct _taos_qall {
   int32_t       numOfItems;
 } STaosQall; 
   
-taos_queue taosOpenQueue(int itemSize) {
+taos_queue taosOpenQueue() {
   
   STaosQueue *queue = (STaosQueue *) calloc(sizeof(STaosQueue), 1);
   if (queue == NULL) {
@@ -57,8 +59,6 @@ taos_queue taosOpenQueue(int itemSize) {
   }
 
   pthread_mutex_init(&queue->mutex, NULL);
-  queue->itemSize = (int32_t)itemSize;
-
   return queue;
 }
 
@@ -83,16 +83,26 @@ void taosCloseQueue(taos_queue param) {
   free(queue);
 }
 
-int taosWriteQitem(taos_queue param, void *item) {
-  STaosQueue *queue = (STaosQueue *)param;
+void *taosAllocateQitem(int size) {
+  STaosQnode *pNode = (STaosQnode *)calloc(sizeof(STaosQnode) + size, 1);
+  if (pNode == NULL) return NULL;
+  return (void *)pNode->item;
+}
 
-  STaosQnode *pNode = (STaosQnode *)calloc(sizeof(STaosQnode) + queue->itemSize, 1);
-  if ( pNode == NULL ) {
-    terrno = TSDB_CODE_NO_RESOURCE;
-    return -1;
-  }
+void taosFreeQitem(void *param) {
+  if (param == NULL) return;
 
-  memcpy(pNode->item, item, queue->itemSize);
+  //pTrace("item:%p is freed", param);
+
+  char *temp = (char *)param;
+  temp -= sizeof(STaosQnode);
+  free(temp);
+}
+
+int taosWriteQitem(taos_queue param, int type, void *item) {
+  STaosQueue *queue = (STaosQueue *)param;
+  STaosQnode *pNode = (STaosQnode *)(((char *)item) - sizeof(STaosQnode));
+  pNode->type = type;
 
   pthread_mutex_lock(&queue->mutex);
 
@@ -107,12 +117,14 @@ int taosWriteQitem(taos_queue param, void *item) {
   queue->numOfItems++;
   if (queue->qset) atomic_add_fetch_32(&queue->qset->numOfItems, 1);
 
+  //pTrace("item:%p is put into queue, items:%d", item, queue->numOfItems);
+
   pthread_mutex_unlock(&queue->mutex);
 
   return 0;
 }
 
-int taosReadQitem(taos_queue param, void *item) {
+int taosReadQitem(taos_queue param, int *type, void **pitem) {
   STaosQueue *queue = (STaosQueue *)param;
   STaosQnode *pNode = NULL;
   int         code = 0;
@@ -121,14 +133,15 @@ int taosReadQitem(taos_queue param, void *item) {
 
   if (queue->head) {
       pNode = queue->head;
-      memcpy(item, pNode->item, queue->itemSize);
+      *pitem = pNode->item;
+      *type = pNode->type;
       queue->head = pNode->next;
       if (queue->head == NULL) 
         queue->tail = NULL;
-      free(pNode);
       queue->numOfItems--;
       if (queue->qset) atomic_sub_fetch_32(&queue->qset->numOfItems, 1);
       code = 1;
+      //pTrace("item:%p is read out from queue, items:%d", *pitem, queue->numOfItems);
   } 
 
   pthread_mutex_unlock(&queue->mutex);
@@ -136,39 +149,42 @@ int taosReadQitem(taos_queue param, void *item) {
   return code;
 }
 
-int taosReadAllQitems(taos_queue param, taos_qall *res) {
+void *taosAllocateQall() {
+  void *p = malloc(sizeof(STaosQall));
+  return p;
+}
+
+void taosFreeQall(void *param) {
+  free(param);
+}
+
+int taosReadAllQitems(taos_queue param, taos_qall p2) {
   STaosQueue *queue = (STaosQueue *)param;
-  STaosQall  *qall = NULL;
+  STaosQall  *qall = (STaosQall *)p2;
   int         code = 0;
 
   pthread_mutex_lock(&queue->mutex);
 
   if (queue->head) {
-    qall = (STaosQall *) calloc(sizeof(STaosQall), 1);
-    if ( qall == NULL ) {
-      terrno = TSDB_CODE_NO_RESOURCE;
-      code = -1;
-    } else {
-      qall->current = queue->head;
-      qall->start = queue->head;
-      qall->numOfItems = queue->numOfItems;
-      qall->itemSize = queue->itemSize;
-      code = qall->numOfItems;
-
-      queue->head = NULL;
-      queue->tail = NULL;
-      queue->numOfItems = 0;
-      if (queue->qset) atomic_sub_fetch_32(&queue->qset->numOfItems, qall->numOfItems);
-    }
+    memset(qall, 0, sizeof(STaosQall));
+    qall->current = queue->head;
+    qall->start = queue->head;
+    qall->numOfItems = queue->numOfItems;
+    qall->itemSize = queue->itemSize;
+    code = qall->numOfItems;
+
+    queue->head = NULL;
+    queue->tail = NULL;
+    queue->numOfItems = 0;
+    if (queue->qset) atomic_sub_fetch_32(&queue->qset->numOfItems, qall->numOfItems);
   } 
 
   pthread_mutex_unlock(&queue->mutex);
   
-  *res = qall;
   return code; 
 }
 
-int taosGetQitem(taos_qall param, void *item) {
+int taosGetQitem(taos_qall param, int *type, void **pitem) {
   STaosQall  *qall = (STaosQall *)param;
   STaosQnode *pNode;
   int         num = 0;
@@ -178,8 +194,10 @@ int taosGetQitem(taos_qall param, void *item) {
     qall->current = pNode->next;
  
   if (pNode) {
-    memcpy(item, pNode->item, qall->itemSize);
+    *pitem = pNode->item;
+    *type = pNode->type;
     num = 1;
+    //pTrace("item:%p is fetched", *pitem);
   }
 
   return num;
@@ -190,19 +208,6 @@ void taosResetQitems(taos_qall param) {
   qall->current = qall->start;
 }
 
-void taosFreeQitems(taos_qall param) {
-  STaosQall  *qall = (STaosQall *)param;
-  STaosQnode *pNode;
-
-  while (qall->current) {
-    pNode = qall->current;
-    qall->current = pNode->next;
-    free(pNode);
-  }
-
-  free(qall);
-}
-
 taos_qset taosOpenQset() {
 
   STaosQset *qset = (STaosQset *) calloc(sizeof(STaosQset), 1);
@@ -221,7 +226,7 @@ void taosCloseQset(taos_qset param) {
   free(qset);
 }
 
-int taosAddIntoQset(taos_qset p1, taos_queue p2) {
+int taosAddIntoQset(taos_qset p1, taos_queue p2, void *ahandle) {
   STaosQueue *queue = (STaosQueue *)p2;
   STaosQset  *qset = (STaosQset *)p1;
 
@@ -230,6 +235,7 @@ int taosAddIntoQset(taos_qset p1, taos_queue p2) {
   pthread_mutex_lock(&qset->mutex);
 
   queue->next = qset->head;
+  queue->ahandle = ahandle;
   qset->head = queue;
   qset->numOfQueues++;
 
@@ -283,7 +289,7 @@ int taosGetQueueNumber(taos_qset param) {
   return ((STaosQset *)param)->numOfQueues;
 }
 
-int taosReadQitemFromQset(taos_qset param, void *item) {
+int taosReadQitemFromQset(taos_qset param, int *type, void **pitem, void **phandle) {
   STaosQset  *qset = (STaosQset *)param;
   STaosQnode *pNode = NULL;
   int         code = 0;
@@ -301,11 +307,12 @@ int taosReadQitemFromQset(taos_qset param, void *item) {
 
     if (queue->head) {
         pNode = queue->head;
-        memcpy(item, pNode->item, queue->itemSize);
+        *pitem = pNode->item;
+        *type = pNode->type;
+        *phandle = queue->ahandle;
         queue->head = pNode->next;
         if (queue->head == NULL) 
           queue->tail = NULL;
-        free(pNode);
         queue->numOfItems--;
         atomic_sub_fetch_32(&qset->numOfItems, 1);
         code = 1;
@@ -318,10 +325,10 @@ int taosReadQitemFromQset(taos_qset param, void *item) {
   return code; 
 }
 
-int taosReadAllQitemsFromQset(taos_qset param, taos_qall *res) {
+int taosReadAllQitemsFromQset(taos_qset param, taos_qall p2, void **phandle) {
   STaosQset  *qset = (STaosQset *)param;
   STaosQueue *queue;
-  STaosQall  *qall = NULL;
+  STaosQall  *qall = (STaosQall *)p2;
   int         code = 0;
 
   for(int i=0; i<qset->numOfQueues; ++i) {
@@ -336,22 +343,17 @@ int taosReadAllQitemsFromQset(taos_qset param, taos_qall *res) {
     pthread_mutex_lock(&queue->mutex);
 
     if (queue->head) {
-      qall = (STaosQall *) calloc(sizeof(STaosQall), 1);
-      if (qall == NULL) {
-        terrno = TSDB_CODE_NO_RESOURCE;
-        code = -1;
-      } else {
-        qall->current = queue->head;
-        qall->start = queue->head;
-        qall->numOfItems = queue->numOfItems;
-        qall->itemSize = queue->itemSize;
-        code = qall->numOfItems;
+      qall->current = queue->head;
+      qall->start = queue->head;
+      qall->numOfItems = queue->numOfItems;
+      qall->itemSize = queue->itemSize;
+      code = qall->numOfItems;
+      *phandle = queue->ahandle;
           
-        queue->head = NULL;
-        queue->tail = NULL;
-        queue->numOfItems = 0;
-        atomic_sub_fetch_32(&qset->numOfItems, qall->numOfItems);
-      }
+      queue->head = NULL;
+      queue->tail = NULL;
+      queue->numOfItems = 0;
+      atomic_sub_fetch_32(&qset->numOfItems, qall->numOfItems);
     } 
 
     pthread_mutex_unlock(&queue->mutex);
@@ -359,8 +361,6 @@ int taosReadAllQitemsFromQset(taos_qset param, taos_qall *res) {
     if (code != 0) break;  
   }
 
-  *res = qall;
-
   return code;
 }
 
diff --git a/src/util/src/tsocket.c b/src/util/src/tsocket.c
index 7ab004646e3094d1a231e30eafaf6a966f0bba8b..86be428af70f6bb04bc72c51f64b2dbb333e493d 100644
--- a/src/util/src/tsocket.c
+++ b/src/util/src/tsocket.c
@@ -330,7 +330,7 @@ int taosOpenTcpClientSocket(char *destIp, uint16_t destPort, char *clientIp) {
   struct sockaddr_in serverAddr, clientAddr;
   int                ret;
 
-  pTrace("open tcp client socket:%s:%d", destIp, destPort);
+  // pTrace("open tcp client socket:%s:%d, local Ip:%s", destIp, destPort, clientIp);
 
   sockFd = (int)socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
 
@@ -362,7 +362,7 @@ int taosOpenTcpClientSocket(char *destIp, uint16_t destPort, char *clientIp) {
   ret = connect(sockFd, (struct sockaddr *)&serverAddr, sizeof(serverAddr));
 
   if (ret != 0) {
-    pError("failed to connect socket, ip:%s, port:%hu, reason: %s", destIp, destPort, strerror(errno));
+    //pError("failed to connect socket, ip:%s, port:%hu, reason: %s", destIp, destPort, strerror(errno));
     taosCloseSocket(sockFd);
     sockFd = -1;
   }