diff --git a/include/util/tcompression.h b/include/util/tcompression.h
index 683a8f2cee..cea648a3a6 100644
--- a/include/util/tcompression.h
+++ b/include/util/tcompression.h
@@ -198,15 +198,6 @@ int32_t tsCompressBigint2(void *pIn, int32_t nIn, int32_t nEle, void *pOut, int3
                           int32_t nBuf);
 int32_t tsDecompressBigint2(void *pIn, int32_t nIn, int32_t nEle, void *pOut, int32_t nOut, uint32_t cmprAlg,
                             void *pBuf, int32_t nBuf);
-// for internal usage
-int32_t getWordLength(char type);
-
-int32_t tsDecompressIntImpl_Hw(const char *const input, const int32_t nelements, char *const output, const char type);
-int32_t tsDecompressFloatImplAvx512(const char *const input, const int32_t nelements, char *const output);
-int32_t tsDecompressFloatImplAvx2(const char *const input, const int32_t nelements, char *const output);
-int32_t tsDecompressTimestampAvx512(const char *const input, const int32_t nelements, char *const output,
-                                    bool bigEndian);
-int32_t tsDecompressTimestampAvx2(const char *const input, const int32_t nelements, char *const output, bool bigEndian);
 
 /*************************************************************************
  *                  STREAM COMPRESSION
diff --git a/source/libs/stream/src/streamMeta.c b/source/libs/stream/src/streamMeta.c
index e7fdb7ae2a..55bb7d1710 100644
--- a/source/libs/stream/src/streamMeta.c
+++ b/source/libs/stream/src/streamMeta.c
@@ -1345,11 +1345,18 @@ int32_t streamMetaStartOneTask(SStreamMeta* pMeta, int64_t streamId, int32_t tas
   }
 
   ASSERT(pTask->status.downstreamReady == 0);
+
+  // avoid initialization and destroy running concurrently.
+  taosThreadMutexLock(&pTask->lock);
   if (pTask->pBackend == NULL) {
     code = pMeta->expandTaskFn(pTask);
+    taosThreadMutexUnlock(&pTask->lock);
+
     if (code != TSDB_CODE_SUCCESS) {
       streamMetaAddFailedTaskSelf(pTask, pInfo->readyTs);
     }
+  } else {
+    taosThreadMutexUnlock(&pTask->lock);
   }
 
   if (code == TSDB_CODE_SUCCESS) {