diff --git a/include/libs/stream/tstream.h b/include/libs/stream/tstream.h
index a9da7d5ef8..bdc2c0a5ec 100644
--- a/include/libs/stream/tstream.h
+++ b/include/libs/stream/tstream.h
@@ -458,7 +458,7 @@ int32_t tDecodeStreamTaskId(SDecoder* pDecoder, STaskId* pTaskId);
 int32_t streamTaskPutDataIntoInputQ(SStreamTask* pTask, SStreamQueueItem* pItem);
 int32_t streamTaskPutDataIntoOutputQ(SStreamTask* pTask, SStreamDataBlock* pBlock);
 int32_t streamTaskPutTranstateIntoInputQ(SStreamTask* pTask);
-bool    streamQueueIsFull(const SStreamQueue* pQueue, bool inputQ);
+bool    streamQueueIsFull(const SStreamQueue* pQueue);
 
 typedef struct {
   SMsgHead head;
@@ -706,6 +706,7 @@ int32_t streamTaskScanHistoryDataComplete(SStreamTask* pTask);
 int32_t streamStartScanHistoryAsync(SStreamTask* pTask, int8_t igUntreated);
 bool    streamHistoryTaskSetVerRangeStep2(SStreamTask* pTask, int64_t latestVer);
 int32_t streamQueueGetNumOfItems(const SStreamQueue* pQueue);
+int32_t streamQueueGetAvailableSpace(const SStreamQueue* pQueue, int32_t* availNum, double* availSize);
 
 // common
 int32_t     streamRestoreParam(SStreamTask* pTask);
diff --git a/source/dnode/vnode/src/tq/tqStreamTask.c b/source/dnode/vnode/src/tq/tqStreamTask.c
index 6448e9d2f7..541d52d5b5 100644
--- a/source/dnode/vnode/src/tq/tqStreamTask.c
+++ b/source/dnode/vnode/src/tq/tqStreamTask.c
@@ -21,7 +21,7 @@
 
 static int32_t doScanWalForAllTasks(SStreamMeta* pStreamMeta, bool* pScanIdle);
 static int32_t setWalReaderStartOffset(SStreamTask* pTask, int32_t vgId);
-static void    handleFillhistoryScanComplete(SStreamTask* pTask, int64_t ver);
+static bool    handleFillhistoryScanComplete(SStreamTask* pTask, int64_t ver);
 
 // extract data blocks(submit/delete) from WAL, and add them into the input queue for all the sources tasks.
 int32_t tqScanWal(STQ* pTq) {
@@ -297,7 +297,7 @@ int32_t setWalReaderStartOffset(SStreamTask* pTask, int32_t vgId) {
 }
 
 // todo handle memory error
-void handleFillhistoryScanComplete(SStreamTask* pTask, int64_t ver) {
+bool handleFillhistoryScanComplete(SStreamTask* pTask, int64_t ver) {
   const char* id = pTask->id.idStr;
   int64_t     maxVer = pTask->dataRange.range.maxVer;
 
@@ -310,12 +310,94 @@ void handleFillhistoryScanComplete(SStreamTask* pTask, int64_t ver) {
       double el = (taosGetTimestampMs() - pTask->execInfo.step2Start) / 1000.0;
       qDebug("s-task:%s scan-history from WAL stage(step 2) ended, elapsed time:%.2fs", id, el);
       /*int32_t code = */streamTaskPutTranstateIntoInputQ(pTask);
-      /*int32_t code = */streamSchedExec(pTask);
+//      /*int32_t code = */streamSchedExec(pTask);
+      return true;
     } else {
       qWarn("s-task:%s fill-history scan WAL, nextProcessVer:%" PRId64 " out of the maximum ver:%" PRId64 ", not scan wal",
             id, ver, maxVer);
     }
   }
+
+  return false;
+}
+
+static bool taskReadyForDataFromWal(SStreamTask* pTask) {
+  // non-source or fill-history tasks don't need to response the WAL scan action.
+  if ((pTask->info.taskLevel != TASK_LEVEL__SOURCE) || (pTask->status.downstreamReady == 0)) {
+    return false;
+  }
+
+  // not in ready state, do not handle the data from wal
+  int32_t status = pTask->status.taskStatus;
+  if (status != TASK_STATUS__NORMAL) {
+    tqTrace("s-task:%s not ready for submit block in wal, status:%s", pTask->id.idStr, streamGetTaskStatusStr(status));
+    return false;
+  }
+
+  // fill-history task has entered into the last phase, no need to anything
+  if ((pTask->info.fillHistory == 1) && pTask->status.appendTranstateBlock) {
+    ASSERT(status == TASK_STATUS__NORMAL);
+    // the maximum version of data in the WAL has reached already, the step2 is done
+    tqDebug("s-task:%s fill-history reach the maximum ver:%" PRId64 ", not scan wal anymore", pTask->id.idStr,
+            pTask->dataRange.range.maxVer);
+    return false;
+  }
+
+  // check if input queue is full or not
+  if (streamQueueIsFull(pTask->inputInfo.queue)) {
+    tqTrace("s-task:%s input queue is full, do nothing", pTask->id.idStr);
+    return false;
+  }
+
+  // the input queue of downstream task is full, so the output is blocked, stopped for a while
+  if (pTask->inputInfo.status == TASK_INPUT_STATUS__BLOCKED) {
+    tqDebug("s-task:%s inputQ is blocked, do nothing", pTask->id.idStr);
+    return false;
+  }
+  
+  return true;
+}
+
+static bool doPutDataIntoInputQFromWal(SStreamTask* pTask, int64_t maxVer, int32_t* numOfItems) {
+  const char* id = pTask->id.idStr;
+  int32_t     numOfNewItems = 0;
+
+  while(1) {
+    if ((pTask->info.fillHistory == 1) && pTask->status.appendTranstateBlock) {
+      *numOfItems += numOfNewItems;
+      return numOfNewItems > 0;
+    }
+
+    SStreamQueueItem* pItem = NULL;
+    int32_t code = extractMsgFromWal(pTask->exec.pWalReader, (void**)&pItem, maxVer, id);
+
+    if ((code != TSDB_CODE_SUCCESS || pItem == NULL)/* && (numOfItems + numOfNewItems == 0)*/) {  // failed, continue
+//      handleFillhistoryScanComplete(pTask, walReaderGetCurrentVer(pTask->exec.pWalReader));
+//      streamMetaReleaseTask(pMeta, pTask);
+//      taosThreadMutexUnlock(&pTask->lock);
+      break;
+    }
+
+    if (pItem != NULL) {
+      code = streamTaskPutDataIntoInputQ(pTask, pItem);
+      if (code == TSDB_CODE_SUCCESS) {
+        numOfNewItems += 1;
+        int64_t ver = walReaderGetCurrentVer(pTask->exec.pWalReader);
+        pTask->chkInfo.nextProcessVer = ver;
+        tqDebug("s-task:%s set the ver:%" PRId64 " from WALReader after extract block from WAL", id, ver);
+
+        bool itemInFillhistory = handleFillhistoryScanComplete(pTask, ver);
+        if (itemInFillhistory) {
+          break;
+        }
+      } else {
+        tqError("s-task:%s append input queue failed, code: too many items, ver:%" PRId64, id, pTask->chkInfo.nextProcessVer);
+      }
+    }
+  }
+
+  *numOfItems += numOfNewItems;
+  return numOfNewItems > 0;
 }
 
 int32_t doScanWalForAllTasks(SStreamMeta* pStreamMeta, bool* pScanIdle) {
@@ -340,45 +422,13 @@ int32_t doScanWalForAllTasks(SStreamMeta* pStreamMeta, bool* pScanIdle) {
   numOfTasks = taosArrayGetSize(pTaskList);
 
   for (int32_t i = 0; i < numOfTasks; ++i) {
-    SStreamTaskId*   pTaskId = taosArrayGet(pTaskList, i);
+    STaskId*     pTaskId = taosArrayGet(pTaskList, i);
     SStreamTask* pTask = streamMetaAcquireTask(pStreamMeta, pTaskId->streamId, pTaskId->taskId);
     if (pTask == NULL) {
       continue;
     }
 
-    int32_t status = pTask->status.taskStatus;
-
-    // non-source or fill-history tasks don't need to response the WAL scan action.
-    if ((pTask->info.taskLevel != TASK_LEVEL__SOURCE) || (pTask->status.downstreamReady == 0)) {
-      streamMetaReleaseTask(pStreamMeta, pTask);
-      continue;
-    }
-
-    const char* pStatus = streamGetTaskStatusStr(status);
-    if (status != TASK_STATUS__NORMAL) {
-      tqTrace("s-task:%s not ready for new submit block from wal, status:%s", pTask->id.idStr, pStatus);
-      streamMetaReleaseTask(pStreamMeta, pTask);
-      continue;
-    }
-
-    if ((pTask->info.fillHistory == 1) && pTask->status.appendTranstateBlock) {
-      ASSERT(status == TASK_STATUS__NORMAL);
-      // the maximum version of data in the WAL has reached already, the step2 is done
-      tqDebug("s-task:%s fill-history reach the maximum ver:%" PRId64 ", not scan wal anymore", pTask->id.idStr,
-              pTask->dataRange.range.maxVer);
-      streamMetaReleaseTask(pStreamMeta, pTask);
-      continue;
-    }
-
-    if (streamQueueIsFull(pTask->inputInfo.queue, true)) {
-      tqTrace("s-task:%s input queue is full, do nothing", pTask->id.idStr);
-      streamMetaReleaseTask(pStreamMeta, pTask);
-      continue;
-    }
-
-    // downstream task has blocked the output, stopped for a while
-    if (pTask->inputInfo.status == TASK_INPUT_STATUS__BLOCKED) {
-      tqDebug("s-task:%s inputQ is blocked, do nothing", pTask->id.idStr);
+    if (!taskReadyForDataFromWal(pTask)) {
       streamMetaReleaseTask(pStreamMeta, pTask);
       continue;
     }
@@ -397,7 +447,7 @@ int32_t doScanWalForAllTasks(SStreamMeta* pStreamMeta, bool* pScanIdle) {
 
     taosThreadMutexLock(&pTask->lock);
 
-    pStatus = streamGetTaskStatusStr(pTask->status.taskStatus);
+    const char* pStatus = streamGetTaskStatusStr(pTask->status.taskStatus);
     if (pTask->status.taskStatus != TASK_STATUS__NORMAL) {
       tqDebug("s-task:%s not ready for submit block from wal, status:%s", pTask->id.idStr, pStatus);
       taosThreadMutexUnlock(&pTask->lock);
@@ -405,33 +455,11 @@ int32_t doScanWalForAllTasks(SStreamMeta* pStreamMeta, bool* pScanIdle) {
       continue;
     }
 
-    SStreamQueueItem* pItem = NULL;
-    code = extractMsgFromWal(pTask->exec.pWalReader, (void**)&pItem, maxVer, pTask->id.idStr);
-
-    if ((code != TSDB_CODE_SUCCESS || pItem == NULL) && (numOfItems == 0)) {  // failed, continue
-      handleFillhistoryScanComplete(pTask, walReaderGetCurrentVer(pTask->exec.pWalReader));
-      streamMetaReleaseTask(pStreamMeta, pTask);
-      taosThreadMutexUnlock(&pTask->lock);
-      continue;
-    }
-
-    if (pItem != NULL) {
-      noDataInWal = false;
-      code = streamTaskPutDataIntoInputQ(pTask, pItem);
-      if (code == TSDB_CODE_SUCCESS) {
-        int64_t ver = walReaderGetCurrentVer(pTask->exec.pWalReader);
-        pTask->chkInfo.nextProcessVer = ver;
-        handleFillhistoryScanComplete(pTask, ver);
-        tqDebug("s-task:%s set the ver:%" PRId64 " from WALReader after extract block from WAL", pTask->id.idStr, ver);
-      } else {
-        tqError("s-task:%s append input queue failed, too many in inputQ, ver:%" PRId64, pTask->id.idStr,
-                pTask->chkInfo.nextProcessVer);
-      }
-    }
-
+    bool hasNewData = doPutDataIntoInputQFromWal(pTask, maxVer, &numOfItems);
     taosThreadMutexUnlock(&pTask->lock);
 
-    if ((code == TSDB_CODE_SUCCESS) || (numOfItems > 0)) {
+    if (/*(code == TSDB_CODE_SUCCESS) || */(numOfItems > 0) || hasNewData) {
+      noDataInWal = false;
       code = streamSchedExec(pTask);
       if (code != TSDB_CODE_SUCCESS) {
         streamMetaReleaseTask(pStreamMeta, pTask);
diff --git a/source/libs/stream/inc/streamInt.h b/source/libs/stream/inc/streamInt.h
index fe4d73b566..2912c2954d 100644
--- a/source/libs/stream/inc/streamInt.h
+++ b/source/libs/stream/inc/streamInt.h
@@ -41,8 +41,7 @@ extern "C" {
 #define STREAM_TASK_KEY_LEN            ((sizeof(int64_t)) << 1)
 
 #define STREAM_TASK_QUEUE_CAPACITY                20480
-#define STREAM_TASK_INPUT_QUEUE_CAPACITY_IN_SIZE  (30)
-#define STREAM_TASK_OUTPUT_QUEUE_CAPACITY_IN_SIZE (50)
+#define STREAM_TASK_QUEUE_CAPACITY_IN_SIZE       (30)
 
 // clang-format off
 #define stFatal(...) do { if (stDebugFlag & DEBUG_FATAL) { taosPrintLog("STM FATAL ", DEBUG_FATAL, 255, __VA_ARGS__); }}     while(0)
diff --git a/source/libs/stream/src/streamDispatch.c b/source/libs/stream/src/streamDispatch.c
index 5b76354dff..7b23366c53 100644
--- a/source/libs/stream/src/streamDispatch.c
+++ b/source/libs/stream/src/streamDispatch.c
@@ -603,7 +603,6 @@ int32_t streamDispatchStreamBlock(SStreamTask* pTask) {
   ASSERT(pBlock->type == STREAM_INPUT__DATA_BLOCK || pBlock->type == STREAM_INPUT__CHECKPOINT_TRIGGER ||
          pBlock->type == STREAM_INPUT__TRANS_STATE);
 
-  int32_t retryCount = 0;
   pTask->execInfo.dispatch += 1;
   pTask->msgInfo.startTs = taosGetTimestampMs();
 
@@ -613,6 +612,7 @@ int32_t streamDispatchStreamBlock(SStreamTask* pTask) {
   } else { // todo handle build dispatch msg failed
   }
 
+  int32_t retryCount = 0;
   while (1) {
     code = sendDispatchMsg(pTask, pTask->msgInfo.pData);
     if (code == TSDB_CODE_SUCCESS) {
diff --git a/source/libs/stream/src/streamMeta.c b/source/libs/stream/src/streamMeta.c
index 71d4beebb1..19cdf9d6bd 100644
--- a/source/libs/stream/src/streamMeta.c
+++ b/source/libs/stream/src/streamMeta.c
@@ -890,8 +890,8 @@ void metaHbToMnode(void* param, void* tmrId) {
         .outputQUsed = SIZE_IN_MiB(streamQueueGetItemSize((*pTask)->outputInfo.queue)),
     };
 
-    entry.inputRate = entry.inputQUsed*100.0/STREAM_TASK_INPUT_QUEUE_CAPACITY_IN_SIZE;
-    entry.outputRate = entry.outputQUsed*100.0/STREAM_TASK_OUTPUT_QUEUE_CAPACITY_IN_SIZE;
+    entry.inputRate = entry.inputQUsed*100.0/STREAM_TASK_QUEUE_CAPACITY_IN_SIZE;
+    entry.outputRate = entry.outputQUsed*100.0/STREAM_TASK_QUEUE_CAPACITY_IN_SIZE;
 
     if ((*pTask)->exec.pWalReader != NULL) {
       entry.offset = walReaderGetCurrentVer((*pTask)->exec.pWalReader);
diff --git a/source/libs/stream/src/streamQueue.c b/source/libs/stream/src/streamQueue.c
index 887220f840..ed2dd42bcb 100644
--- a/source/libs/stream/src/streamQueue.c
+++ b/source/libs/stream/src/streamQueue.c
@@ -102,14 +102,13 @@ void streamQueueProcessFail(SStreamQueue* queue) {
   atomic_store_8(&queue->status, STREAM_QUEUE__FAILED);
 }
 
-bool streamQueueIsFull(const SStreamQueue* pQueue, bool inputQ) {
+bool streamQueueIsFull(const SStreamQueue* pQueue) {
   int32_t numOfItems = streamQueueGetNumOfItems(pQueue);
   if (numOfItems >= STREAM_TASK_QUEUE_CAPACITY) {
     return true;
   }
 
-  int32_t threshold = (inputQ) ? STREAM_TASK_INPUT_QUEUE_CAPACITY_IN_SIZE : STREAM_TASK_OUTPUT_QUEUE_CAPACITY_IN_SIZE;
-  return (SIZE_IN_MiB(taosQueueMemorySize(pQueue->pQueue)) >= threshold);
+  return (SIZE_IN_MiB(taosQueueMemorySize(pQueue->pQueue)) >= STREAM_TASK_QUEUE_CAPACITY_IN_SIZE);
 }
 
 int32_t streamQueueGetNumOfItems(const SStreamQueue* pQueue) {
@@ -119,6 +118,14 @@ int32_t streamQueueGetNumOfItems(const SStreamQueue* pQueue) {
   return numOfItems1 + numOfItems2;
 }
 
+int32_t streamQueueGetAvailableSpace(const SStreamQueue* pQueue, int32_t* availNum, double* availSize) {
+  int32_t num = streamQueueGetNumOfItems(pQueue);
+  *availNum = STREAM_TASK_QUEUE_CAPACITY - num;
+
+  *availSize = STREAM_TASK_QUEUE_CAPACITY_IN_SIZE - taosQueueMemorySize(pQueue->pQueue);
+  return 0;
+}
+
 // todo: fix it: data in Qall is not included here
 int32_t streamQueueGetItemSize(const SStreamQueue* pQueue) {
   return taosQueueMemorySize(pQueue->pQueue);
@@ -264,11 +271,11 @@ int32_t streamTaskPutDataIntoInputQ(SStreamTask* pTask, SStreamQueueItem* pItem)
 
   if (type == STREAM_INPUT__DATA_SUBMIT) {
     SStreamDataSubmit* px = (SStreamDataSubmit*)pItem;
-    if ((pTask->info.taskLevel == TASK_LEVEL__SOURCE) && streamQueueIsFull(pTask->inputInfo.queue, true)) {
+    if ((pTask->info.taskLevel == TASK_LEVEL__SOURCE) && streamQueueIsFull(pTask->inputInfo.queue)) {
       double size = SIZE_IN_MiB(taosQueueMemorySize(pQueue));
       stTrace(
           "s-task:%s inputQ is full, capacity(size:%d num:%dMiB), current(blocks:%d, size:%.2fMiB) stop to push data",
-          pTask->id.idStr, STREAM_TASK_QUEUE_CAPACITY, STREAM_TASK_INPUT_QUEUE_CAPACITY_IN_SIZE, total, size);
+          pTask->id.idStr, STREAM_TASK_QUEUE_CAPACITY, STREAM_TASK_QUEUE_CAPACITY_IN_SIZE, total, size);
       streamDataSubmitDestroy(px);
       taosFreeQitem(pItem);
       return -1;
@@ -291,11 +298,11 @@ int32_t streamTaskPutDataIntoInputQ(SStreamTask* pTask, SStreamQueueItem* pItem)
            msgLen, ver, total, size + SIZE_IN_MiB(msgLen));
   } else if (type == STREAM_INPUT__DATA_BLOCK || type == STREAM_INPUT__DATA_RETRIEVE ||
              type == STREAM_INPUT__REF_DATA_BLOCK) {
-    if (streamQueueIsFull(pTask->inputInfo.queue, true)) {
+    if (streamQueueIsFull(pTask->inputInfo.queue)) {
       double size = SIZE_IN_MiB(taosQueueMemorySize(pQueue));
 
       stTrace("s-task:%s input queue is full, capacity:%d size:%d MiB, current(blocks:%d, size:%.2fMiB) abort",
-             pTask->id.idStr, STREAM_TASK_QUEUE_CAPACITY, STREAM_TASK_INPUT_QUEUE_CAPACITY_IN_SIZE, total, size);
+             pTask->id.idStr, STREAM_TASK_QUEUE_CAPACITY, STREAM_TASK_QUEUE_CAPACITY_IN_SIZE, total, size);
       destroyStreamDataBlock((SStreamDataBlock*)pItem);
       return -1;
     }
@@ -345,7 +352,7 @@ int32_t streamTaskPutDataIntoInputQ(SStreamTask* pTask, SStreamQueueItem* pItem)
 int32_t streamTaskPutDataIntoOutputQ(SStreamTask* pTask, SStreamDataBlock* pBlock) {
   STaosQueue* pQueue = pTask->outputInfo.queue->pQueue;
 
-  while (streamQueueIsFull(pTask->inputInfo.queue, false)) {
+  while (streamQueueIsFull(pTask->inputInfo.queue)) {
     if (streamTaskShouldStop(&pTask->status)) {
       stInfo("s-task:%s discard result block due to task stop", pTask->id.idStr);
       return TSDB_CODE_STREAM_EXEC_CANCELLED;