diff --git a/examples/rust b/examples/rust
deleted file mode 160000
index 7ed7a97715388fa144718764d6bf20f9bfc29a12..0000000000000000000000000000000000000000
--- a/examples/rust
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 7ed7a97715388fa144718764d6bf20f9bfc29a12
diff --git a/include/libs/stream/tstream.h b/include/libs/stream/tstream.h
index 0dd137d5327b5992d740a3e18e01e0320b599596..f5074becece062b293a13d4e9c68313c83fff116 100644
--- a/include/libs/stream/tstream.h
+++ b/include/libs/stream/tstream.h
@@ -513,6 +513,7 @@ SStreamTask* streamMetaGetTask(SStreamMeta* pMeta, int32_t taskId);
 int32_t streamMetaBegin(SStreamMeta* pMeta);
 int32_t streamMetaCommit(SStreamMeta* pMeta);
 int32_t streamMetaRollBack(SStreamMeta* pMeta);
+int32_t streamLoadTasks(SStreamMeta* pMeta);
 
 #ifdef __cplusplus
 }
diff --git a/source/libs/stream/src/streamExec.c b/source/libs/stream/src/streamExec.c
index 4a4d67b89aa03ae86017cf6dea94a5a274b5aae6..7512f792c1a6a631421f60497a5db95c46d9a788 100644
--- a/source/libs/stream/src/streamExec.c
+++ b/source/libs/stream/src/streamExec.c
@@ -19,23 +19,23 @@ static int32_t streamTaskExecImpl(SStreamTask* pTask, const void* data, SArray*
   void* exec = pTask->exec.executor;
 
   // set input
-  SStreamQueueItem* pItem = (SStreamQueueItem*)data;
+  const SStreamQueueItem* pItem = (const SStreamQueueItem*)data;
   if (pItem->type == STREAM_INPUT__GET_RES) {
-    SStreamTrigger* pTrigger = (SStreamTrigger*)data;
+    const SStreamTrigger* pTrigger = (const SStreamTrigger*)data;
     qSetMultiStreamInput(exec, pTrigger->pBlock, 1, STREAM_INPUT__DATA_BLOCK);
   } else if (pItem->type == STREAM_INPUT__DATA_SUBMIT) {
     ASSERT(pTask->taskLevel == TASK_LEVEL__SOURCE);
-    SStreamDataSubmit* pSubmit = (SStreamDataSubmit*)data;
+    const SStreamDataSubmit* pSubmit = (const SStreamDataSubmit*)data;
     qDebug("task %d %p set submit input %p %p %d 1", pTask->taskId, pTask, pSubmit, pSubmit->data, *pSubmit->dataRef);
     qSetMultiStreamInput(exec, pSubmit->data, 1, STREAM_INPUT__DATA_SUBMIT);
   } else if (pItem->type == STREAM_INPUT__DATA_BLOCK || pItem->type == STREAM_INPUT__DATA_RETRIEVE) {
-    SStreamDataBlock* pBlock = (SStreamDataBlock*)data;
-    SArray*           blocks = pBlock->blocks;
+    const SStreamDataBlock* pBlock = (const SStreamDataBlock*)data;
+    SArray*                 blocks = pBlock->blocks;
     qDebug("task %d %p set ssdata input", pTask->taskId, pTask);
     qSetMultiStreamInput(exec, blocks->pData, blocks->size, STREAM_INPUT__DATA_BLOCK);
   } else if (pItem->type == STREAM_INPUT__MERGED_SUBMIT) {
-    SStreamMergedSubmit* pMerged = (SStreamMergedSubmit*)data;
-    SArray*              blocks = pMerged->reqs;
+    const SStreamMergedSubmit* pMerged = (const SStreamMergedSubmit*)data;
+    SArray*                    blocks = pMerged->reqs;
     qDebug("task %d %p set submit input (merged), batch num: %d", pTask->taskId, pTask, (int32_t)blocks->size);
     qSetMultiStreamInput(exec, blocks->pData, blocks->size, STREAM_INPUT__MERGED_SUBMIT);
   } else {
@@ -51,8 +51,8 @@ static int32_t streamTaskExecImpl(SStreamTask* pTask, const void* data, SArray*
     }
     if (output == NULL) {
       if (pItem->type == STREAM_INPUT__DATA_RETRIEVE) {
-        SSDataBlock       block = {0};
-        SStreamDataBlock* pRetrieveBlock = (SStreamDataBlock*)data;
+        SSDataBlock             block = {0};
+        const SStreamDataBlock* pRetrieveBlock = (const SStreamDataBlock*)data;
         ASSERT(taosArrayGetSize(pRetrieveBlock->blocks) == 1);
         assignOneDataBlock(&block, taosArrayGet(pRetrieveBlock->blocks, 0));
         block.info.type = STREAM_PULL_OVER;
diff --git a/source/libs/stream/src/streamMeta.c b/source/libs/stream/src/streamMeta.c
index 8faa22d6439487bad9c76ab5ad554489b752976e..b74e8386280a9a3a90da87dd12d37806a588cfa5 100644
--- a/source/libs/stream/src/streamMeta.c
+++ b/source/libs/stream/src/streamMeta.c
@@ -48,8 +48,18 @@ SStreamMeta* streamMetaOpen(const char* path, void* ahandle, FTaskExpand expandF
   pMeta->ahandle = ahandle;
   pMeta->expandFunc = expandFunc;
 
+  if (streamLoadTasks(pMeta) < 0) {
+    goto _err;
+  }
   return pMeta;
+
 _err:
+  if (pMeta->path) taosMemoryFree(pMeta->path);
+  if (pMeta->pTasks) taosHashCleanup(pMeta->pTasks);
+  if (pMeta->pStateDb) tdbTbClose(pMeta->pStateDb);
+  if (pMeta->pTaskDb) tdbTbClose(pMeta->pTaskDb);
+  if (pMeta->db) tdbClose(pMeta->db);
+  taosMemoryFree(pMeta);
   return NULL;
 }
 
diff --git a/source/libs/stream/src/streamRecover.c b/source/libs/stream/src/streamRecover.c
index 28693d15a6179636a81baa891b78338a7c4bd839..2b5af0684dc975dd8cbbb164c6e18218502bf6a8 100644
--- a/source/libs/stream/src/streamRecover.c
+++ b/source/libs/stream/src/streamRecover.c
@@ -130,14 +130,13 @@ int32_t tDecodeSStreamMultiVgCheckpointInfo(SDecoder* pDecoder, SStreamMultiVgCh
   return 0;
 }
 
-int32_t streamCheckSinkLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
+int32_t streamSaveStateInfo(SStreamMeta* pMeta, SStreamTask* pTask) {
   void* buf = NULL;
 
   ASSERT(pTask->taskLevel == TASK_LEVEL__SINK);
-  int32_t sz = taosArrayGetSize(pTask->checkpointInfo);
 
   SStreamMultiVgCheckpointInfo checkpoint;
-  checkpoint.checkpointId = 0;
+  checkpoint.checkpointId = atomic_fetch_add_32(&pTask->nextCheckId, 1);
   checkpoint.checkTs = taosGetTimestampMs();
   checkpoint.streamId = pTask->streamId;
   checkpoint.taskId = pTask->taskId;
@@ -169,16 +168,21 @@ int32_t streamCheckSinkLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
     goto FAIL;
   }
 
+  int32_t sz = taosArrayGetSize(pTask->checkpointInfo);
+  for (int32_t i = 0; i < sz; i++) {
+    SStreamCheckpointInfo* pCheck = taosArrayGet(pTask->checkpointInfo, i);
+    pCheck->stateSaveVer = pCheck->stateProcessedVer;
+  }
+
   taosMemoryFree(buf);
   return 0;
 FAIL:
   if (buf) taosMemoryFree(buf);
   return -1;
+  return 0;
 }
 
-int32_t streamRecoverSinkLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
-  ASSERT(pTask->taskLevel == TASK_LEVEL__SINK);
-  // load status
+int32_t streamLoadStateInfo(SStreamMeta* pMeta, SStreamTask* pTask) {
   void*   pVal = NULL;
   int32_t vLen = 0;
   if (tdbTbGet(pMeta->pStateDb, &pTask->taskId, sizeof(void*), &pVal, &vLen) < 0) {
@@ -196,29 +200,71 @@ int32_t streamRecoverSinkLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
   return 0;
 }
 
-int32_t streamCheckAggLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
+int32_t streamSaveSinkLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
+  ASSERT(pTask->taskLevel == TASK_LEVEL__SINK);
+  return streamSaveStateInfo(pMeta, pTask);
+}
+
+int32_t streamRecoverSinkLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
+  ASSERT(pTask->taskLevel == TASK_LEVEL__SINK);
+  return streamLoadStateInfo(pMeta, pTask);
+}
+
+int32_t streamSaveAggLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
   ASSERT(pTask->taskLevel == TASK_LEVEL__AGG);
-  // save and copy state
+  // TODO save and copy state
+
   // save state info
+  if (streamSaveStateInfo(pMeta, pTask) < 0) {
+    return -1;
+  }
+  return 0;
+}
+
+int32_t streamFetchSinkStatus(SStreamTask* pTask) {
+  ASSERT(pTask->taskLevel != TASK_LEVEL__SINK);
+  // set self status to recover_phase1
+  // build fetch status msg
+  // send fetch msg
+  return 0;
+}
+
+int32_t streamProcessFetchStatusRsp(SStreamMeta* pMeta, SStreamTask* pTask, void* msg) {
+  // if failed, set timer and retry
+  // if successful
+  // add rsp state to partial recover hash
+  // if complete, begin actual recover
   return 0;
 }
 
 int32_t streamRecoverAggLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
   ASSERT(pTask->taskLevel == TASK_LEVEL__AGG);
-  // try recover sink level
-  // after all sink level recovered, choose current state backend to recover
+  // recover sink level
+  // after all sink level recovered
+  // choose suitable state to recover
   return 0;
 }
 
-int32_t streamCheckSourceLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
+int32_t streamSaveSourceLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
   ASSERT(pTask->taskLevel == TASK_LEVEL__SOURCE);
-  // try recover agg level
-  //
+  // TODO: save and copy state
   return 0;
 }
 
 int32_t streamRecoverSourceLevel(SStreamMeta* pMeta, SStreamTask* pTask) {
   ASSERT(pTask->taskLevel == TASK_LEVEL__SOURCE);
+  // if totLevel == 3
+  // fetch agg state
+  // recover from local state to agg state, not send msg
+  // recover from agg state to most recent log v1
+  // enable input queue, set status recover_phase2
+  // recover from v1 to queue msg v2, set status normal
+
+  // if totLevel == 2
+  // fetch sink state
+  // recover from local state to sink state v1, send msg
+  // enable input queue, set status recover_phase2
+  // recover from v1 to queue msg v2, set status normal
   return 0;
 }
 
diff --git a/tools/taos-tools b/tools/taos-tools
deleted file mode 160000
index 3c7dafeea3e558968165b73bee0f51024898e3da..0000000000000000000000000000000000000000
--- a/tools/taos-tools
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 3c7dafeea3e558968165b73bee0f51024898e3da