diff --git a/src/tsdb/src/tsdbMain.c b/src/tsdb/src/tsdbMain.c
index 55f80a8d22b03ac0a922e9361cf2e65766b158d5..88a404135a000fd2ff1fd054ee498092e4815917 100644
--- a/src/tsdb/src/tsdbMain.c
+++ b/src/tsdb/src/tsdbMain.c
@@ -924,10 +924,12 @@ static int tsdbCommitToFile(STsdbRepo *pRepo, int fid, SSkipListIterator **iters
 
     // Loop to write the data in the cache to files. If no data to write, just break the loop 
     int maxRowsToRead = pCfg->maxRowsPerFileBlock * 4 / 5;
+    int nLoop = 0;
     while (true) {
       int rowsRead = tsdbReadRowsFromCache(pIter, maxKey, maxRowsToRead, pDataCols);
       ASSERT(rowsRead >= 0);
       if (pDataCols->numOfPoints == 0) break;
+      nLoop++;
 
       ASSERT(dataColsKeyFirst(pDataCols) >= minKey && dataColsKeyFirst(pDataCols) <= maxKey);
       ASSERT(dataColsKeyLast(pDataCols) >= minKey && dataColsKeyLast(pDataCols) <= maxKey);
diff --git a/src/tsdb/src/tsdbRWHelper.c b/src/tsdb/src/tsdbRWHelper.c
index e24a3c5786e9355d332878d90f6ef529d63fb434..2656334567ee2316b044b3aa2dd6d536f1073547 100644
--- a/src/tsdb/src/tsdbRWHelper.c
+++ b/src/tsdb/src/tsdbRWHelper.c
@@ -281,9 +281,7 @@ int tsdbWriteDataBlock(SRWHelper *pHelper, SDataCols *pDataCols) {
 
   // Load the SCompInfo part if neccessary
   ASSERT(helperHasState(pHelper, TSDB_HELPER_TABLE_SET));
-  if (!helperHasState(pHelper, TSDB_HELPER_INFO_LOAD) && (pIdx->offset > 0)) {
-    if (tsdbLoadCompInfo(pHelper, NULL) < 0) goto _err;
-  }
+  if (tsdbLoadCompInfo(pHelper, NULL) < 0) goto _err;
 
   if (pIdx->offset == 0 || (!pIdx->hasLast && keyFirst > pIdx->maxKey)) {  // Just append as a super block
     ASSERT(pHelper->hasOldLastBlock == false);
@@ -370,6 +368,7 @@ int tsdbWriteCompInfo(SRWHelper *pHelper) {
   if (!helperHasState(pHelper, TSDB_HELPER_INFO_LOAD)) {
     if (pIdx->offset > 0) {
       pIdx->offset = lseek(pHelper->files.nHeadF.fd, 0, SEEK_END);
+      ASSERT(pIdx->offset > TSDB_FILE_HEAD_SIZE);
       if (pIdx->offset < 0) return -1;
 
       if (tsendfile(pHelper->files.nHeadF.fd, pHelper->files.headF.fd, NULL, pIdx->len) < pIdx->len) return -1;
@@ -377,6 +376,7 @@ int tsdbWriteCompInfo(SRWHelper *pHelper) {
   } else {
     taosCalcChecksumAppend(0, (uint8_t *)pHelper->pCompInfo, pIdx->len);
     pIdx->offset = lseek(pHelper->files.nHeadF.fd, 0, SEEK_END);
+    ASSERT(pIdx->offset > TSDB_FILE_HEAD_SIZE);
     if (pIdx->offset < 0) return -1;
 
     if (twrite(pHelper->files.nHeadF.fd, (void *)(pHelper->pCompInfo), pIdx->len) < pIdx->len) return -1;
@@ -919,15 +919,18 @@ static int tsdbInsertSuperBlock(SRWHelper *pHelper, SCompBlock *pCompBlock, int
   }
 
   // Memmove if needed
-  int tsize = pIdx->len - (sizeof(SCompData) + sizeof(SCompCol) * blkIdx);
+  int tsize = pIdx->len - (sizeof(SCompInfo) + sizeof(SCompBlock) * blkIdx);
   if (tsize > 0) {
-    memmove((void *)((char *)pHelper->pCompInfo + sizeof(SCompData) + sizeof(SCompBlock) * (blkIdx + 1)),
-            (void *)((char *)pHelper->pCompInfo + sizeof(SCompData) + sizeof(SCompBlock) * blkIdx), tsize);
+    ASSERT(sizeof(SCompInfo) + sizeof(SCompBlock) * (blkIdx + 1) < tsizeof(pHelper->pCompInfo));
+    ASSERT(sizeof(SCompInfo) + sizeof(SCompBlock) * (blkIdx + 1) + tsize <= tsizeof(pHelper->pCompInfo));
+    memmove((void *)((char *)pHelper->pCompInfo + sizeof(SCompInfo) + sizeof(SCompBlock) * (blkIdx + 1)),
+            (void *)((char *)pHelper->pCompInfo + sizeof(SCompInfo) + sizeof(SCompBlock) * blkIdx), tsize);
   }
   pHelper->pCompInfo->blocks[blkIdx] = *pCompBlock;
 
   pIdx->numOfSuperBlocks++;
   pIdx->len += sizeof(SCompBlock);
+  ASSERT(pIdx->len <= tsizeof(pHelper->pCompInfo));
   pIdx->maxKey = pHelper->pCompInfo->blocks[pIdx->numOfSuperBlocks - 1].keyLast;
   pIdx->hasLast = pHelper->pCompInfo->blocks[pIdx->numOfSuperBlocks - 1].last;