diff --git a/source/libs/qworker/src/qworker.c b/source/libs/qworker/src/qworker.c
index 375851ff18bad3a0c59e297fbe9a859b72bd0bd0..57bb73c500cb0285b1bcd064b6d0129c99540a13 100644
--- a/source/libs/qworker/src/qworker.c
+++ b/source/libs/qworker/src/qworker.c
@@ -254,6 +254,19 @@ int32_t qwAcquireTaskCtx(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_
   return TSDB_CODE_SUCCESS;
 }
 
+int32_t qwGetTaskCtx(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t tId, SQWTaskCtx **ctx) {
+  char id[sizeof(qId) + sizeof(tId)] = {0};
+  QW_SET_QTID(id, qId, tId);
+  
+  *ctx = taosHashGet(mgmt->ctxHash, id, sizeof(id));
+  if (NULL == (*ctx)) {
+    QW_TASK_ELOG("ctx not in ctxHash, id:%s", id);
+    QW_ERR_RET(TSDB_CODE_QRY_RES_CACHE_NOT_EXIST);
+  }
+
+  return TSDB_CODE_SUCCESS;
+}
+
 int32_t qwAddTaskCtxImpl(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t tId, int32_t rwType, int32_t status, SQWTaskCtx **ctx) {
   char id[sizeof(qId) + sizeof(tId)] = {0};
   QW_SET_QTID(id, qId, tId);
@@ -294,19 +307,6 @@ int32_t qwAddTaskCtx(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t tI
   QW_RET(qwAddTaskCtxImpl(QW_FPARAMS(), 0, 0, NULL));
 }
 
-int32_t qwGetTaskCtx(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t tId, SQWTaskCtx **ctx) {
-  char id[sizeof(qId) + sizeof(tId)] = {0};
-  QW_SET_QTID(id, qId, tId);
-  
-  *ctx = taosHashGet(mgmt->ctxHash, id, sizeof(id));
-  if (NULL == (*ctx)) {
-    QW_TASK_ELOG("ctx not in ctxHash, id:%s", id);
-    QW_ERR_RET(TSDB_CODE_QRY_RES_CACHE_NOT_EXIST);
-  }
-
-  return TSDB_CODE_SUCCESS;
-
-}
 
 
 int32_t qwAddAcquireTaskCtx(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t tId, int32_t rwType, SQWTaskCtx **ctx) {
@@ -322,16 +322,33 @@ void qwReleaseTaskCtx(int32_t rwType, SQWorkerMgmt *mgmt) {
   QW_UNLOCK(rwType, &mgmt->ctxLock);
 }
 
+void qwFreeTaskHandle(QW_FPARAMS_DEF, SQWTaskCtx *ctx) {  
+  // RC WARNING
+  qTaskInfo_t taskHandle = atomic_load_ptr(&ctx->taskHandle);
+  if (taskHandle && atomic_val_compare_exchange_ptr(&ctx->taskHandle, taskHandle, NULL)) {
+    qDestroyTask(taskHandle);
+  }
+}
 
-void qwFreeTask(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t tId, SQWTaskCtx *ctx) {
-  if (ctx->taskHandle) {
-    qDestroyTask(ctx->taskHandle);
-    ctx->taskHandle = NULL;
+int32_t qwKillTaskHandle(QW_FPARAMS_DEF, SQWTaskCtx *ctx) {
+  int32_t code = 0;
+  // RC WARNING
+  qTaskInfo_t taskHandle = atomic_load_ptr(&ctx->taskHandle);
+  if (taskHandle && atomic_val_compare_exchange_ptr(&ctx->taskHandle, taskHandle, NULL)) {
+    code = qKillTask(taskHandle);
+    atomic_store_ptr(&ctx->taskHandle, taskHandle);
   }
 
-  // TODO
-  if (ctx->sinkHandle) {
+  QW_RET(code);
+}
+
 
+void qwFreeTask(QW_FPARAMS_DEF, SQWTaskCtx *ctx) {
+  qwFreeTaskHandle(QW_FPARAMS(), ctx);
+  
+  if (ctx->sinkHandle) {
+    dsDestroyDataSinker(ctx->sinkHandle);
+    ctx->sinkHandle = NULL;
   }
 }
 
@@ -425,7 +442,7 @@ int32_t qwDropTask(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t tId,
   SQWTaskCtx *ctx = NULL;
   bool locked = false;
 
-  QW_ERR_JRET(qwAddGetTaskCtx(QW_FPARAMS(), QW_READ, &ctx));
+  QW_ERR_JRET(qwAddGetTaskCtx(QW_FPARAMS(), &ctx));
   
   QW_LOCK(QW_WRITE, &ctx->lock);
 
@@ -437,9 +454,7 @@ int32_t qwDropTask(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t tId,
   }
 
   if (QW_IN_EXECUTOR(ctx)) {
-    if (ctx->taskHandle) {
-      QW_ERR_JRET(qKillTask(ctx->taskHandle));
-    }
+    QW_ERR_JRET(qwKillTaskHandle(QW_FPARAMS(), ctx));
     
     QW_ERR_JRET(qwUpdateTaskStatus(QW_FPARAMS(), JOB_TASK_STATUS_DROPPING));
   } else if (ctx->phase > 0) {
@@ -587,7 +602,7 @@ int32_t qwHandleTaskEvent(QW_FPARAMS_DEF, int32_t phase, SQWPhaseInput *input, S
 
   switch (phase) {
     case QW_PHASE_PRE_QUERY: {
-      QW_ERR_JRET(qwAddGetTaskCtx(QW_FPARAMS(), QW_READ, &ctx));
+      QW_ERR_JRET(qwAddGetTaskCtx(QW_FPARAMS(), &ctx));
             
       ctx->phase = phase;
 
@@ -607,7 +622,6 @@ int32_t qwHandleTaskEvent(QW_FPARAMS_DEF, int32_t phase, SQWPhaseInput *input, S
         output->needStop = true;
         
         QW_ERR_JRET(qwAddTaskStatus(QW_FPARAMS(), JOB_TASK_STATUS_CANCELLED));
-        qwFreeTask(QW_FPARAMS(), ctx);
         
         QW_SET_EVENT_PROCESSED(ctx, QW_EVENT_CANCEL);
         
@@ -620,7 +634,7 @@ int32_t qwHandleTaskEvent(QW_FPARAMS_DEF, int32_t phase, SQWPhaseInput *input, S
       break;
     }
     case QW_PHASE_POST_QUERY: {
-      QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), QW_READ, &ctx));
+      QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), &ctx));
       
       QW_LOCK(QW_WRITE, &ctx->lock);
       
@@ -702,7 +716,7 @@ int32_t qwHandleTaskEvent(QW_FPARAMS_DEF, int32_t phase, SQWPhaseInput *input, S
       break;
     }    
     case QW_PHASE_POST_CQUERY: {
-      QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), QW_READ, &ctx));
+      QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), &ctx));
       
       QW_LOCK(QW_WRITE, &ctx->lock);
       
@@ -738,7 +752,7 @@ int32_t qwHandleTaskEvent(QW_FPARAMS_DEF, int32_t phase, SQWPhaseInput *input, S
       break;
     }    
     case QW_PHASE_PRE_FETCH: {
-      QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), QW_READ, &ctx));
+      QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), &ctx));
       
       QW_LOCK(QW_WRITE, &ctx->lock);
       
@@ -786,7 +800,7 @@ int32_t qwHandleTaskEvent(QW_FPARAMS_DEF, int32_t phase, SQWPhaseInput *input, S
       break;
     }    
     case QW_PHASE_POST_FETCH: {
-      QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), QW_READ, &ctx));
+      QW_ERR_JRET(qwGetTaskCtx(QW_FPARAMS(), &ctx));
       
       QW_LOCK(QW_WRITE, &ctx->lock);
       
@@ -983,7 +997,8 @@ int32_t qwProcessCQuery(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t
       
       if ((!sOutput.queryEnd) && (DS_BUF_LOW == sOutput.bufStatus || DS_BUF_EMPTY == sOutput.bufStatus)) {    
         QW_TASK_DLOG("task not end, need to continue, bufStatus:%d", sOutput.bufStatus);
-      
+        
+        // RC WARNING
         atomic_store_8(&ctx->queryContinue, 1);
       }
       
@@ -1061,6 +1076,7 @@ int32_t qwProcessFetch(SQWorkerMgmt *mgmt, uint64_t sId, uint64_t qId, uint64_t
     QW_LOCK(QW_WRITE, &ctx->lock);
     locked = true;
 
+    // RC WARNING
     if (QW_IN_EXECUTOR(ctx)) {
       atomic_store_8(&ctx->queryContinue, 1);
     } else if (0 == atomic_load_8(&ctx->inQueue)) {