fix(stream): refactor the tasks restart mechanism.

include/libs/stream/tstream.h

@@ -390,6 +390,7 @@ typedef struct SStreamMeta {
   tmr_h         hbTmr;
   SMgmtInfo     mgmtInfo;
 
+  int32_t closedTask;
   int32_t chkptNotReadyTasks;
 
   int64_t  chkpId;

source/dnode/vnode/src/tq/tq.c

@@ -1855,13 +1855,12 @@ int32_t tqProcessStreamTaskCheckpointReadyMsg(STQ* pTq, SRpcMsg* pMsg) {
 }
 
 int32_t tqProcessTaskUpdateReq(STQ* pTq, SRpcMsg* pMsg) {
+  bool         restartTasks = false;
   SStreamMeta* pMeta = pTq->pStreamMeta;
-
-  int32_t vgId = TD_VID(pTq->pVnode);
-  char*   msg = POINTER_SHIFT(pMsg->pCont, sizeof(SMsgHead));
-  int32_t len = pMsg->contLen - sizeof(SMsgHead);
-  bool    startTask = vnodeIsRoleLeader(pTq->pVnode);  // in case of follower, do not launch task
-  SRpcMsg rsp = {.info = pMsg->info, .code = TSDB_CODE_SUCCESS};
+  int32_t      vgId = TD_VID(pTq->pVnode);
+  char*        msg = POINTER_SHIFT(pMsg->pCont, sizeof(SMsgHead));
+  int32_t      len = pMsg->contLen - sizeof(SMsgHead);
+  SRpcMsg      rsp = {.info = pMsg->info, .code = TSDB_CODE_SUCCESS};
 
   SStreamTaskNodeUpdateMsg req = {0};
 
@@ -1884,34 +1883,52 @@ int32_t tqProcessTaskUpdateReq(STQ* pTq, SRpcMsg* pMsg) {
 
   tqDebug("s-task:%s receive task nodeEp update msg from mnode", pTask->id.idStr);
   streamTaskUpdateEpsetInfo(pTask, req.pNodeList);
+  streamTaskStop(pTask);
 
-  SStreamTask* pHistoryTask = NULL;
-  if (pTask->historyTaskId.taskId != 0) {
-    pHistoryTask = streamMetaAcquireTask(pMeta, pTask->historyTaskId.streamId, pTask->historyTaskId.taskId);
-    if (pHistoryTask != NULL) {
-      tqDebug("s-task:%s fill-history task handle task update along with related stream task", pHistoryTask->id.idStr);
-      streamTaskUpdateEpsetInfo(pHistoryTask, req.pNodeList);
+  taosWLockLatch(&pMeta->lock);
 
-      streamTaskRestart(pHistoryTask, NULL, startTask);
-      streamMetaReleaseTask(pMeta, pHistoryTask);
-    } else {
-      tqError("vgId:%d failed to get fill-history task:0x%x when handling task update, it may have been dropped",
-              pMeta->vgId, pTask->historyTaskId.taskId);
-      streamMetaReleaseTask(pMeta, pTask);
-    }
-  }
+  int32_t numOfCount = streamMetaGetNumOfTasks(pMeta);
+  pMeta->closedTask += 1;
 
-  streamTaskRestart(pTask, NULL, startTask);
+  tqDebug("s-task:%s task nodeEp update completed", pTask->id.idStr);
   streamMetaReleaseTask(pMeta, pTask);
 
-  int32_t code = rsp.code;
+  // all tasks are closed, now let's restart the stream meta
+  if (pMeta->closedTask == numOfCount) {
+    if (streamMetaCommit(pMeta) < 0) {
+      //     persist to disk
+    }
+    restartTasks = true;
+    pMeta->closedTask = 0;  // reset value
+  }
+
+  taosWUnLockLatch(&pMeta->lock);
 
 _end:
   tDecoderClear(&decoder);
   tmsgSendRsp(&rsp);
 
-  tqDebug("s-task:%s task nodeEp update completed", pTask->id.idStr);
-  return code;
+  if (restartTasks) {
+    tqDebug("vgId:%d all tasks are stopped, restart them", vgId);
+
+    streamMetaClose(pTask->pMeta);
+
+    pTq->pStreamMeta = streamMetaOpen(pTq->path, pTq, (FTaskExpand*)tqExpandTask, pTq->pVnode->config.vgId, -1);
+    if (pTq->pStreamMeta == NULL) {
+      return -1;
+    }
+
+    if (streamLoadTasks(pTq->pStreamMeta) < 0) {
+      return -1;
+    }
+
+    if (vnodeIsRoleLeader(pTq->pVnode) && !tsDisableStream) {
+      vInfo("vgId:%d, restart to all stream tasks", vgId);
+      tqCheckStreamStatus(pTq);
+    }
+  }
+
+  return rsp.code;
 }
 
 int32_t tqProcessTaskStopReq(STQ* pTq, SRpcMsg* pMsg) {