fix(tsdb/cache): fix block index ref releasing

source/dnode/vnode/src/tsdb/tsdbCache.c

@@ -35,7 +35,11 @@ _err:
 static void tsdbCloseBICache(STsdb *pTsdb) {
   SLRUCache *pCache = pTsdb->biCache;
   if (pCache) {
+    int32_t elems = taosLRUCacheGetElems(pCache);
+    tsdbTrace("vgId:%d, elems: %d", TD_VID(pTsdb->pVnode), elems);
     taosLRUCacheEraseUnrefEntries(pCache);
+    elems = taosLRUCacheGetElems(pCache);
+    tsdbTrace("vgId:%d, elems: %d", TD_VID(pTsdb->pVnode), elems);
 
     taosLRUCacheCleanup(pCache);
 
@@ -819,7 +823,12 @@ static int32_t getNextRowFromFS(void *iter, TSDBROW **ppRow, bool *pIgnoreEarlie
        * &state->blockIdx);
        */
       state->pBlockIdx = taosArraySearch(state->aBlockIdx, state->pBlockIdxExp, tCmprBlockIdx, TD_EQ);
-      if (!state->pBlockIdx) { /*
+      if (!state->pBlockIdx) {
+        tsdbBICacheRelease(state->pTsdb->biCache, state->aBlockIdxHandle);
+
+        state->aBlockIdxHandle = NULL;
+        state->aBlockIdx = NULL;
+        /*
          tsdbDataFReaderClose(state->pDataFReader);
          *state->pDataFReader = NULL;
          resetLastBlockLoadInfo(state->pLoadInfo);*/
@@ -1936,6 +1945,7 @@ int32_t tsdbCacheGetBlockIdx(SLRUCache *pCache, SDataFReader *pFileReader, LRUHa
     taosThreadMutexUnlock(&pTsdb->biMutex);
   }
 
+  tsdbTrace("bi cache:%p, ref", pCache);
   *handle = h;
 
   return code;
@@ -1945,6 +1955,7 @@ int32_t tsdbBICacheRelease(SLRUCache *pCache, LRUHandle *h) {
   int32_t code = 0;
 
   taosLRUCacheRelease(pCache, h, false);
+  tsdbTrace("bi cache:%p, release", pCache);
 
   return code;
 }

tests/script/tsim/parser/last_cache.sim

@@ -53,7 +53,7 @@ sql insert into tbc values ("2021-05-11 10:12:29",36,  37, NULL, -4005)
 sql insert into tbd values ("2021-05-11 10:12:29",NULL,NULL,NULL,NULL )
 
 run tsim/parser/last_cache_query.sim
-
+sql flush database $db
 system sh/exec.sh -n dnode1 -s stop -x SIGINT
 
 system sh/exec.sh -n dnode1 -s start