diff --git a/include/libs/monitor/clientMonitor.h b/include/libs/monitor/clientMonitor.h
index 4c7ab6f65a..0085173ecd 100644
--- a/include/libs/monitor/clientMonitor.h
+++ b/include/libs/monitor/clientMonitor.h
@@ -38,6 +38,13 @@ typedef enum {
   SLOW_LOG_READ_QUIT = 3,
 } SLOW_LOG_QUEUE_TYPE;
 
+static char* queueTypeStr[] = {
+  "SLOW_LOG_WRITE",
+  "SLOW_LOG_READ_RUNNING",
+  "SLOW_LOG_READ_BEGINNIG",
+  "SLOW_LOG_READ_QUIT"
+};
+
 #define SLOW_LOG_SEND_SIZE_MAX 1024*1024
 
 typedef struct {
@@ -65,7 +72,7 @@ typedef struct {
 } MonitorSlowLogData;
 
 void            monitorClose();
-void            monitorInit();
+int32_t         monitorInit();
 
 void            monitorClientSQLReqInit(int64_t clusterKey);
 void            monitorClientSlowQueryInit(int64_t clusterId);
diff --git a/source/client/src/clientEnv.c b/source/client/src/clientEnv.c
index 3a821768f8..ecfa1e3392 100644
--- a/source/client/src/clientEnv.c
+++ b/source/client/src/clientEnv.c
@@ -864,10 +864,15 @@ void taos_init_imp(void) {
   initQueryModuleMsgHandle();
 
   if (taosConvInit() != 0) {
+    tscInitRes = -1;
     tscError("failed to init conv");
     return;
   }
-
+  if (monitorInit() != 0){
+    tscInitRes = -1;
+    tscError("failed to init monitor");
+    return;
+  }
   rpcInit();
 
   SCatalogCfg cfg = {.maxDBCacheNum = 100, .maxTblCacheNum = 100};
@@ -891,7 +896,6 @@ void taos_init_imp(void) {
   taosThreadMutexInit(&appInfo.mutex, NULL);
 
   tscCrashReportInit();
-  monitorInit();
 
   tscDebug("client is initialized successfully");
 }
diff --git a/source/client/src/clientMonitor.c b/source/client/src/clientMonitor.c
index 479ea76fe3..d1a9897caa 100644
--- a/source/client/src/clientMonitor.c
+++ b/source/client/src/clientMonitor.c
@@ -18,6 +18,7 @@ int32_t     quitCnt = 0;
 tsem2_t     monitorSem;
 STaosQueue* monitorQueue;
 SHashObj*   monitorSlowLogHash;
+char        tmpSlowLogPath[PATH_MAX] = {0};
 
 static int32_t getSlowLogTmpDir(char* tmpPath, int32_t size){
   if (tsTempDir == NULL) {
@@ -453,6 +454,10 @@ static int64_t getFileSize(char* path){
 }
 
 static int32_t sendSlowLog(int64_t clusterId, char* data, TdFilePtr pFile, int64_t offset, SLOW_LOG_QUEUE_TYPE type, char* fileName, void* pTransporter, SEpSet *epSet){
+  if (data == NULL){
+    taosMemoryFree(fileName);
+    return -1;
+  }
   MonitorSlowLogData* pParam = taosMemoryMalloc(sizeof(MonitorSlowLogData));
   if(pParam == NULL){
     taosMemoryFree(data);
@@ -468,18 +473,26 @@ static int32_t sendSlowLog(int64_t clusterId, char* data, TdFilePtr pFile, int64
   return sendReport(pTransporter, epSet, data, MONITOR_TYPE_SLOW_LOG, pParam);
 }
 
-static void monitorSendSlowLogAtBeginning(int64_t clusterId, char** fileName, TdFilePtr pFile, int64_t offset, void* pTransporter, SEpSet *epSet){
+static int32_t monitorReadSend(int64_t clusterId, TdFilePtr pFile, int64_t* offset, int64_t size, SLOW_LOG_QUEUE_TYPE type, char* fileName){
+  SAppInstInfo* pInst = getAppInstByClusterId(clusterId);
+  if(pInst == NULL){
+    tscError("failed to get app instance by clusterId:%" PRId64, clusterId);
+    return -1;
+  }
+  SEpSet ep = getEpSet_s(&pInst->mgmtEp);
+  char* data = readFile(pFile, offset, size);
+  return sendSlowLog(clusterId, data, (type == SLOW_LOG_READ_BEGINNIG ? pFile : NULL), *offset, type, fileName, pInst->pTransporter, &ep);
+}
+
+static void monitorSendSlowLogAtBeginning(int64_t clusterId, char** fileName, TdFilePtr pFile, int64_t offset){
   int64_t  size = getFileSize(*fileName);
   if(size <= offset){
     processFileInTheEnd(pFile, *fileName);
     tscDebug("[monitor] monitorSendSlowLogAtBeginning delete file:%s", *fileName);
   }else{
-    char* data = readFile(pFile, &offset, size);
-    if(data != NULL){
-      sendSlowLog(clusterId, data, pFile, offset, SLOW_LOG_READ_BEGINNIG, *fileName, pTransporter, epSet);
-      *fileName = NULL;
-    }
-    tscDebug("[monitor] monitorSendSlowLogAtBeginning send slow log file:%p, data:%s", pFile, data);
+    int32_t code = monitorReadSend(clusterId, pFile, &offset, size, SLOW_LOG_READ_BEGINNIG, *fileName);
+    tscDebug("[monitor] monitorSendSlowLogAtBeginning send slow log clusterId:%"PRId64",ret:%d", clusterId, code);
+    *fileName = NULL;
   }
 }
 
@@ -500,17 +513,8 @@ static void monitorSendSlowLogAtRunning(int64_t clusterId){
     tscDebug("[monitor] monitorSendSlowLogAtRunning truncate file to 0 file:%p", pClient->pFile);
     pClient->offset = 0;
   }else{
-    SAppInstInfo* pInst = getAppInstByClusterId(clusterId);
-    if(pInst == NULL){
-      tscError("failed to get app instance by clusterId:%" PRId64, clusterId);
-      return;
-    }
-    SEpSet ep = getEpSet_s(&pInst->mgmtEp);
-    char* data = readFile(pClient->pFile, &pClient->offset, size);
-    if(data != NULL){
-      sendSlowLog(clusterId, data, pClient->pFile, pClient->offset, SLOW_LOG_READ_RUNNING, NULL, pInst->pTransporter, &ep);
-    }
-    tscDebug("[monitor] monitorSendSlowLogAtRunning send slow log:%s", data);
+    int32_t code = monitorReadSend(clusterId, pClient->pFile, &pClient->offset, size, SLOW_LOG_READ_RUNNING, NULL);
+    tscDebug("[monitor] monitorSendSlowLogAtRunning send slow log clusterId:%"PRId64",ret:%d", clusterId, code);
   }
 }
 
@@ -532,16 +536,8 @@ static bool monitorSendSlowLogAtQuit(int64_t clusterId) {
       return true;
     }
   }else{
-    SAppInstInfo* pInst = getAppInstByClusterId(clusterId);
-    if(pInst == NULL) {
-      return true;
-    }
-    SEpSet ep = getEpSet_s(&pInst->mgmtEp);
-    char* data = readFile(pClient->pFile, &pClient->offset, size);
-    if(data != NULL){
-      sendSlowLog(clusterId, data, pClient->pFile, pClient->offset, SLOW_LOG_READ_QUIT, NULL, pInst->pTransporter, &ep);
-    }
-    tscInfo("[monitor] monitorSendSlowLogAtQuit send slow log:%s", data);
+    int32_t code = monitorReadSend(clusterId, pClient->pFile, &pClient->offset, size, SLOW_LOG_READ_QUIT, NULL);
+    tscDebug("[monitor] monitorSendSlowLogAtQuit send slow log clusterId:%"PRId64",ret:%d", clusterId, code);
   }
   return false;
 }
@@ -558,16 +554,11 @@ static void   monitorSendAllSlowLogAtQuit(){
       pClient->pFile = NULL;
     }else if(pClient->offset == 0){
       int64_t* clusterId = (int64_t*)taosHashGetKey(pIter, NULL);
-      SAppInstInfo* pInst = getAppInstByClusterId(*clusterId);
-      if(pInst == NULL) {
-        continue;
-      }
-      SEpSet ep = getEpSet_s(&pInst->mgmtEp);
-      char* data = readFile(pClient->pFile, &pClient->offset, size);
-      if(data != NULL && sendSlowLog(*clusterId, data, NULL, pClient->offset, SLOW_LOG_READ_QUIT, NULL, pInst->pTransporter, &ep) == 0){
+      int32_t code = monitorReadSend(*clusterId, pClient->pFile, &pClient->offset, size, SLOW_LOG_READ_QUIT, NULL);
+      tscDebug("[monitor] monitorSendAllSlowLogAtQuit send slow log clusterId:%"PRId64",ret:%d", *clusterId, code);
+      if (code == 0){
         quitCnt ++;
       }
-      tscInfo("[monitor] monitorSendAllSlowLogAtQuit send slow log :%s", data);
     }
   }
 }
@@ -613,12 +604,8 @@ static void monitorSendAllSlowLog(){
         }
         continue;
       }
-      SEpSet ep = getEpSet_s(&pInst->mgmtEp);
-      char* data = readFile(pClient->pFile, &pClient->offset, size);
-      if(data != NULL){
-        sendSlowLog(*clusterId, data, NULL, pClient->offset, SLOW_LOG_READ_RUNNING, NULL, pInst->pTransporter, &ep);
-      }
-      tscDebug("[monitor] monitorSendAllSlowLog send slow log :%s", data);
+      int32_t code = monitorReadSend(*clusterId, pClient->pFile, &pClient->offset, size, SLOW_LOG_READ_RUNNING, NULL);
+      tscDebug("[monitor] monitorSendAllSlowLog send slow log clusterId:%"PRId64",ret:%d", *clusterId, code);
     }
   }
 }
@@ -631,7 +618,7 @@ static void monitorSendAllSlowLogFromTempDir(int64_t clusterId){
     return;
   }
   char namePrefix[PATH_MAX] = {0};
-  if (snprintf(namePrefix, sizeof(namePrefix), "%s%"PRIx64, TD_TMP_FILE_PREFIX, pInst->clusterId) < 0) {
+  if (snprintf(namePrefix, sizeof(namePrefix), "%s%"PRIx64, TD_TMP_FILE_PREFIX, clusterId) < 0) {
     tscError("failed to generate slow log file name prefix");
     return;
   }
@@ -656,7 +643,7 @@ static void monitorSendAllSlowLogFromTempDir(int64_t clusterId){
     if (strcmp(name, ".") == 0 ||
         strcmp(name, "..") == 0 ||
         strstr(name, namePrefix) == NULL) {
-      tscInfo("skip file:%s, for cluster id:%"PRIx64, name, pInst->clusterId);
+      tscInfo("skip file:%s, for cluster id:%"PRIx64, name, clusterId);
       continue;
     }
 
@@ -672,9 +659,8 @@ static void monitorSendAllSlowLogFromTempDir(int64_t clusterId){
       taosCloseFile(&pFile);
       continue;
     }
-    SEpSet ep = getEpSet_s(&pInst->mgmtEp);
     char *tmp = taosStrdup(filename);
-    monitorSendSlowLogAtBeginning(pInst->clusterId, &tmp, pFile, 0, pInst->pTransporter, &ep);
+    monitorSendSlowLogAtBeginning(clusterId, &tmp, pFile, 0);
     taosMemoryFree(tmp);
   }
 
@@ -690,28 +676,6 @@ static void* monitorThreadFunc(void *param){
   }
 #endif
 
-  char tmpPath[PATH_MAX] = {0};
-  if (getSlowLogTmpDir(tmpPath, sizeof(tmpPath)) < 0){
-    return NULL;
-  }
-
-  if (taosMulModeMkDir(tmpPath, 0777, true) != 0) {
-    terrno = TAOS_SYSTEM_ERROR(errno);
-    printf("failed to create dir:%s since %s", tmpPath, terrstr());
-    return NULL;
-  }
-
-  if (tsem2_init(&monitorSem, 0, 0) != 0) {
-    tscError("sem init error since %s", terrstr());
-    return NULL;
-  }
-
-  monitorQueue = taosOpenQueue();
-  if(monitorQueue == NULL){
-    tscError("open queue error since %s", terrstr());
-    return NULL;
-  }
-
   if (-1 != atomic_val_compare_exchange_32(&slowLogFlag, -1, 0)) {
     return NULL;
   }
@@ -738,16 +702,12 @@ static void* monitorThreadFunc(void *param){
     if (slowLogData != NULL) {
       if (slowLogData->type == SLOW_LOG_READ_BEGINNIG){
         if(slowLogData->pFile != NULL){
-          SAppInstInfo* pInst = getAppInstByClusterId(slowLogData->clusterId);
-          if(pInst != NULL) {
-            SEpSet ep = getEpSet_s(&pInst->mgmtEp);
-            monitorSendSlowLogAtBeginning(slowLogData->clusterId, &(slowLogData->fileName), slowLogData->pFile, slowLogData->offset, pInst->pTransporter, &ep);
-          }
+          monitorSendSlowLogAtBeginning(slowLogData->clusterId, &(slowLogData->fileName), slowLogData->pFile, slowLogData->offset);
         }else{
           monitorSendAllSlowLogFromTempDir(slowLogData->clusterId);
         }
       } else if(slowLogData->type == SLOW_LOG_WRITE){
-        monitorWriteSlowLog2File(slowLogData, tmpPath);
+        monitorWriteSlowLog2File(slowLogData, tmpSlowLogPath);
       } else if(slowLogData->type == SLOW_LOG_READ_RUNNING){
         monitorSendSlowLogAtRunning(slowLogData->clusterId);
       } else if(slowLogData->type == SLOW_LOG_READ_QUIT){
@@ -799,27 +759,59 @@ static void tscMonitorStop() {
   }
 }
 
-void monitorInit() {
+int32_t monitorInit() {
   tscInfo("[monitor] tscMonitor init");
   monitorCounterHash = (SHashObj*)taosHashInit(64, taosGetDefaultHashFunction(TSDB_DATA_TYPE_BIGINT), false, HASH_ENTRY_LOCK);
   if (monitorCounterHash == NULL) {
     tscError("failed to create monitorCounterHash");
+    terrno = TSDB_CODE_OUT_OF_MEMORY;
+    return -1;
   }
   taosHashSetFreeFp(monitorCounterHash, destroyMonitorClient);
 
   monitorSlowLogHash = (SHashObj*)taosHashInit(64, taosGetDefaultHashFunction(TSDB_DATA_TYPE_BIGINT), false, HASH_ENTRY_LOCK);
   if (monitorSlowLogHash == NULL) {
     tscError("failed to create monitorSlowLogHash");
+    terrno = TSDB_CODE_OUT_OF_MEMORY;
+    return -1;
   }
   taosHashSetFreeFp(monitorSlowLogHash, destroySlowLogClient);
 
   monitorTimer = taosTmrInit(0, 0, 0, "MONITOR");
   if (monitorTimer == NULL) {
     tscError("failed to create monitor timer");
+    terrno = TSDB_CODE_OUT_OF_MEMORY;
+    return -1;
+  }
+
+  if (getSlowLogTmpDir(tmpSlowLogPath, sizeof(tmpSlowLogPath)) < 0){
+    terrno = TSDB_CODE_TSC_INTERNAL_ERROR;
+    return -1;
+  }
+
+  if (taosMulModeMkDir(tmpSlowLogPath, 0777, true) != 0) {
+    terrno = TAOS_SYSTEM_ERROR(errno);
+    tscError("failed to create dir:%s since %s", tmpSlowLogPath, terrstr());
+    return -1;
+  }
+
+  if (tsem2_init(&monitorSem, 0, 0) != 0) {
+    terrno = TAOS_SYSTEM_ERROR(errno);
+    tscError("sem init error since %s", terrstr());
+    return -1;
+  }
+
+  monitorQueue = taosOpenQueue();
+  if(monitorQueue == NULL){
+    tscError("open queue error since %s", terrstr());
+    return -1;
   }
 
   taosInitRWLatch(&monitorLock);
-  tscMonitortInit();
+  if (tscMonitortInit() != 0){
+    return -1;
+  }
+  return 0;
 }
 
 void monitorClose() {
@@ -844,10 +836,7 @@ int32_t monitorPutData2MonitorQueue(MonitorSlowLogData data){
     return -1;
   }
   *slowLogData = data;
-  tscDebug("[monitor] write slow log to queue, clusterId:%"PRIx64 " type:%d", slowLogData->clusterId, slowLogData->type);
-  while (atomic_load_32(&slowLogFlag) == -1) {
-    taosMsleep(5);
-  }
+  tscDebug("[monitor] write slow log to queue, clusterId:%"PRIx64 " type:%s, data:%s", slowLogData->clusterId, queueTypeStr[slowLogData->type], slowLogData->data);
   if (taosWriteQitem(monitorQueue, slowLogData) == 0){
     tsem2_post(&monitorSem);
   }else{
diff --git a/source/client/src/clientMsgHandler.c b/source/client/src/clientMsgHandler.c
index e5baa7137e..d587deffc5 100644
--- a/source/client/src/clientMsgHandler.c
+++ b/source/client/src/clientMsgHandler.c
@@ -154,13 +154,14 @@ int32_t processConnectRsp(void* param, SDataBuf* pMsg, int32_t code) {
   if(taosHashGet(appInfo.pInstMapByClusterId, &connectRsp.clusterId, LONG_BYTES) == NULL){
     if(taosHashPut(appInfo.pInstMapByClusterId, &connectRsp.clusterId, LONG_BYTES, &pTscObj->pAppInfo, POINTER_BYTES) != 0){
       tscError("failed to put appInfo into appInfo.pInstMapByClusterId");
+    }else{
+      MonitorSlowLogData data = {0};
+      data.clusterId = pTscObj->pAppInfo->clusterId;
+      data.type = SLOW_LOG_READ_BEGINNIG;
+      monitorPutData2MonitorQueue(data);
+      monitorClientSlowQueryInit(connectRsp.clusterId);
+      monitorClientSQLReqInit(connectRsp.clusterId);
     }
-    MonitorSlowLogData data = {0};
-    data.clusterId = pTscObj->pAppInfo->clusterId;
-    data.type = SLOW_LOG_READ_BEGINNIG;
-    monitorPutData2MonitorQueue(data);
-    monitorClientSlowQueryInit(connectRsp.clusterId);
-    monitorClientSQLReqInit(connectRsp.clusterId);
   }
 
   taosThreadMutexLock(&clientHbMgr.lock);