diff --git a/src/tsdb/src/tsdbRWHelper.c b/src/tsdb/src/tsdbRWHelper.c
index eebe0b6b4614d2ba0b1420772bdedc1b758065d3..eeb212fe95ba3e0023c60181a4c1cae2cde0f9d3 100644
--- a/src/tsdb/src/tsdbRWHelper.c
+++ b/src/tsdb/src/tsdbRWHelper.c
@@ -443,6 +443,11 @@ int tsdbWriteCompIdx(SRWHelper *pHelper) {
   for (uint32_t i = 0; i < pHelper->config.maxTables; i++) {
     SCompIdx *pCompIdx = pHelper->pCompIdx + i;
     if (pCompIdx->offset > 0) {
+      int drift = POINTER_DISTANCE(buf, pHelper->pBuffer);
+      if (tsizeof(pHelper->pBuffer) - drift < 128) {
+        pHelper->pBuffer = trealloc(pHelper->pBuffer, tsizeof(pHelper->pBuffer)*2);
+      }
+      buf = POINTER_SHIFT(pHelper->pBuffer, drift);
       buf = taosEncodeVariant32(buf, i);
       buf = tsdbEncodeSCompIdx(buf, pCompIdx);
     }
@@ -469,6 +474,7 @@ int tsdbLoadCompIdx(SRWHelper *pHelper, void *target) {
       ASSERT(pFile->info.offset > TSDB_FILE_HEAD_SIZE);
 
       if (lseek(fd, pFile->info.offset, SEEK_SET) < 0) return -1;
+      if ((pHelper->pBuffer = trealloc(pHelper->pBuffer, pFile->info.len)) == NULL) return -1;
       if (tread(fd, (void *)(pHelper->pBuffer), pFile->info.len) < pFile->info.len)
         return -1;
       if (!taosCheckChecksumWhole((uint8_t *)(pHelper->pBuffer), pFile->info.len)) {
diff --git a/src/util/inc/tutil.h b/src/util/inc/tutil.h
index 5dcb6e406f5c8dccd989ec0e2e8e1d2542177020..255680496a4bbe0b4e10efaed7e06676577e340c 100644
--- a/src/util/inc/tutil.h
+++ b/src/util/inc/tutil.h
@@ -46,6 +46,7 @@ extern "C" {
 
 // Pointer p drift right by b bytes
 #define POINTER_SHIFT(p, b) ((void *)((char *)(p) + (b)))
+#define POINTER_DISTANCE(p1, p2) ((char *)(p1) - (char *)(p2)) 
 
 #ifndef NDEBUG
 #define ASSERT(x) assert(x)