diff --git a/src/tsdb/src/tsdbBuffer.c b/src/tsdb/src/tsdbBuffer.c
index f27af3b722..70f8e054f8 100644
--- a/src/tsdb/src/tsdbBuffer.c
+++ b/src/tsdb/src/tsdbBuffer.c
@@ -123,8 +123,6 @@ SListNode *tsdbAllocBufBlockFromPool(STsdbRepo *pRepo) {
     pthread_cond_wait(&(pBufPool->poolNotEmpty), &(pRepo->mutex));
   }
 
-  ASSERT(!POOL_IS_EMPTY(pBufPool));
-
   SListNode *    pNode = tdListPopHead(pBufPool->bufBlockList);
   STsdbBufBlock *pBufBlock = NULL;
   tdListNodeGetData(pBufPool->bufBlockList, pNode, (void *)(&pBufBlock));
diff --git a/src/tsdb/src/tsdbMemTable.c b/src/tsdb/src/tsdbMemTable.c
index 55fda4e116..cfb405f518 100644
--- a/src/tsdb/src/tsdbMemTable.c
+++ b/src/tsdb/src/tsdbMemTable.c
@@ -97,7 +97,6 @@ int tsdbRefMemTable(STsdbRepo *pRepo, SMemTable *pMemTable) {
 
 // Need to lock the repository
 int tsdbUnRefMemTable(STsdbRepo *pRepo, SMemTable *pMemTable) {
-  ASSERT(IS_REPO_LOCKED(pRepo));
   ASSERT(pMemTable != NULL);
 
   if (T_REF_DEC(pMemTable) == 0) {
@@ -105,12 +104,15 @@ int tsdbUnRefMemTable(STsdbRepo *pRepo, SMemTable *pMemTable) {
     STsdbBufPool *pBufPool = pRepo->pPool;
 
     SListNode *pNode = NULL;
+    // TODO: check the correctness of this code part
+    if (tsdbLockRepo(pRepo) < 0) return -1;
     while ((pNode = tdListPopHead(pMemTable->bufBlockList)) != NULL) {
       tdListAppendNode(pBufPool->bufBlockList, pNode);
       if (pthread_cond_signal(&pBufPool->poolNotEmpty) != 0) {
         // TODO
       }
     }
+    if (tsdbUnlockRepo(pRepo) < 0) return -1;
 
     for (int i = 0; i < pCfg->maxTables; i++) {
       if (pMemTable->tData[i] != NULL) {
@@ -127,7 +129,8 @@ int tsdbUnRefMemTable(STsdbRepo *pRepo, SMemTable *pMemTable) {
 
 // ---------------- LOCAL FUNCTIONS ----------------
 static FORCE_INLINE STsdbBufBlock *tsdbGetCurrBufBlock(STsdbRepo *pRepo) {
-  if (pRepo == NULL || pRepo->mem == NULL) return NULL;
+  ASSERT(pRepo != NULL);
+  if (pRepo->mem == NULL) return NULL;
 
   SListNode *pNode = listTail(pRepo->mem);
   if (pNode == NULL) return NULL;
@@ -141,45 +144,40 @@ static FORCE_INLINE STsdbBufBlock *tsdbGetCurrBufBlock(STsdbRepo *pRepo) {
 static void *tsdbAllocBytes(STsdbRepo *pRepo, int bytes) {
   STsdbCfg *     pCfg = &pRepo->config;
   STsdbBufBlock *pBufBlock = tsdbGetCurrBufBlock(pRepo);
+  int            code = 0;
 
   if (pBufBlock != NULL && pBufBlock->remain < bytes) {
-    if (listNEles(pRepo->mem) >= pCfg->totalBlocks / 2) {  // need to trigger commit
-      if (pRepo->imem != NULL) {
-        if (pRepo->commit) pthread_join(pRepo->commitThread, NULL);
-
-        ASSERT(pRepo->commit == 0);
-
-        SMemTable *pIMem = pRepo->imem;
-        if (tsdbLockRepo(pRepo) < 0) {
-          // TODO
+    if (listNEles(pRepo->mem) >= pCfg->totalBlocks / 2) {  // need to commit mem
+      if (pRepo->imem) {
+        code = pthread_join(pRepo->commitThread, NULL);
+        if (code != 0) {
+          tsdbError("vgId:%d failed to thread join since %s", REPO_ID(pRepo), strerror(errno));
+          terrno = TAOS_SYSTEM_ERROR(errno);
           return NULL;
         }
-
-        pRepo->imem = pRepo->mem;
-        pRepo->mem = NULL;
-        pRepo->commit = 1;
-        if (pthread_create(&pRepo->commitThread, NULL, tsdbCommitData, (void *)pRepo) != 0) {
-          // TODO
-          tsdbUnlockRepo(pRepo);
-          return NULL;
-        }
-        if (tsdbUnlockRepo(pRepo) < 0) {
-          // TODO
-          return NULL;
-        }
-
-        tsdbUnRefMemTable(pRepo, pIMem);
       }
-    } else {
-      if (tsdbLockRepo(pRepo) < 0) {
-        tsdbFreeMemTable(pMemTable);
+
+      ASSERT(pRepo->commit == 0);
+      SMemTable *pImem = pRepo->imem;
+
+      if (tsdbLockRepo(pRepo) < 0) return NULL;
+      pRepo->imem = pRepo->mem;
+      pRepo->mem = NULL;
+      pRepo->commit = 1;
+      code = pthread_create(&pRepo->commitThread, NULL, tsdbCommitData, (void *)pRepo);
+      if (code != 0) {
+        tsdbError("vgId:%d failed to create commit thread since %s", REPO_ID(pRepo), strerror(errno));
+        terrno = TAOS_SYSTEM_ERROR(code);
+        tsdbUnlockRepo(pRepo);
         return NULL;
       }
+      if (tsdbUnlockRepo(pRepo) < 0) return NULL;
 
+      if (pImem && tsdbUnRefMemTable(pRepo, pImem) < 0) return NULL;
+    } else {
+      if (tsdbLockRepo(pRepo) < 0) return NULL;
       SListNode *pNode = tsdbAllocBufBlockFromPool(pRepo);
-      tdListAppendNode(pMemTable->bufBlockList, pNode);
-      pRepo->mem = pMemTable;
-
+      tdListAppendNode(pRepo->mem->bufBlockList, pNode);
       if (tsdbUnlockRepo(pRepo) < 0) return NULL;
     }
   }