diff --git a/packaging/tools/set_core.sh b/packaging/tools/set_core.sh
index 083b0516dbb03daafe8c19548b7fac494af7d24a..9f6c5ae9d12f15a72d2beafcfb2cd28f88a10dc6 100755
--- a/packaging/tools/set_core.sh
+++ b/packaging/tools/set_core.sh
@@ -2,19 +2,39 @@
 #
 # This file is used to set config for core when taosd crash
 
+# Color setting
+RED='\033[0;31m'
+GREEN='\033[1;32m'
+GREEN_DARK='\033[0;32m'
+GREEN_UNDERLINE='\033[4;32m'
+NC='\033[0m'
+
 set -e
 # set -x
+corePath=$1
 
 csudo=""
 if command -v sudo > /dev/null; then
   csudo="sudo"
 fi
 
-#ulimit -c unlimited
+if [[ ! -n ${corePath} ]]; then
+  echo -e -n "${GREEN}Please enter a file directory to save the coredump file${NC}:"
+	read corePath
+  while true; do
+    if [[ ! -z "$corePath" ]]; then
+      break
+    else
+      read -p "Please enter a file directory to save the coredump file:" corePath
+    fi
+  done
+fi
+
+ulimit -c unlimited
 ${csudo} sed -i '/ulimit -c unlimited/d' /etc/profile ||:
 ${csudo} sed -i '$a\ulimit -c unlimited' /etc/profile ||:
 source /etc/profile
 
-${csudo} mkdir -p /coredump  ||:
-${csudo} sysctl -w kernel.core_pattern='/coredump/core-%e-%p'  ||:
-${csudo} echo '/coredump/core-%e-%p' | ${csudo} tee /proc/sys/kernel/core_pattern  ||:
+${csudo} mkdir -p ${corePath}  ||:
+${csudo} sysctl -w kernel.core_pattern=${corePath}/core-%e-%p  ||:
+${csudo} echo "${corePath}/core-%e-%p" | ${csudo} tee /proc/sys/kernel/core_pattern  ||:
diff --git a/src/kit/taosdump/taosdump.c b/src/kit/taosdump/taosdump.c
index 588d21574b6d4c07b746ee487b0449c705186298..60707f22e297e3cd253d88cc9bed962dd36dacd1 100644
--- a/src/kit/taosdump/taosdump.c
+++ b/src/kit/taosdump/taosdump.c
@@ -332,6 +332,9 @@ static error_t parse_opt(int key, char *arg, struct argp_state *state) {
       break;
     case 'N':
       arguments->data_batch = atoi(arg);
+      if (arguments->data_batch >= INT16_MAX) {
+        arguments->data_batch = INT16_MAX - 1;
+      } 
       break;
     case 'L': 
     {
diff --git a/src/query/inc/qHistogram.h b/src/query/inc/qHistogram.h
index c904d0ec9b0d6f6dc9404222a64d29dd878c9407..7742d151a06456a8b3c10e8b1f0aeba6203a28b7 100644
--- a/src/query/inc/qHistogram.h
+++ b/src/query/inc/qHistogram.h
@@ -67,7 +67,7 @@ void tHistogramDestroy(SHistogramInfo** pHisto);
 
 void tHistogramPrint(SHistogramInfo* pHisto);
 
-//int32_t histoBinarySearch(SHistBin* pEntry, int32_t len, double val);
+int32_t histoBinarySearch(SHistBin* pEntry, int32_t len, double val);
 
 SHeapEntry* tHeapCreate(int32_t numOfEntries);
 void tHeapSort(SHeapEntry* pEntry, int32_t len);
diff --git a/src/query/src/qHistogram.c b/src/query/src/qHistogram.c
index bd979f1244953f747513fbc5b2f820eb34e85213..6ae6ede972455ce07c657a4d215b21727c1b1db5 100644
--- a/src/query/src/qHistogram.c
+++ b/src/query/src/qHistogram.c
@@ -120,7 +120,6 @@
 //}
 
 static int32_t histogramCreateBin(SHistogramInfo* pHisto, int32_t index, double val);
-static int32_t histoBinarySearch(SHistBin* pEntry, int32_t len, double val);
 
 SHistogramInfo* tHistogramCreate(int32_t numOfEntries) {
   /* need one redundant slot */
diff --git a/src/query/tests/histogramTest.cpp b/src/query/tests/histogramTest.cpp
index 4a5f7fbbbed18b0a2c2cd7fff7ad3101cfa11c41..82fd4bcf9907eeb1286f9b6d0976e541e7b1a16b 100644
--- a/src/query/tests/histogramTest.cpp
+++ b/src/query/tests/histogramTest.cpp
@@ -21,19 +21,19 @@ TEST(testCase, histogram_binary_search) {
     pHisto->elems[i].val = i;
   }
 
-  int32_t idx = vnodeHistobinarySearch(pHisto->elems, pHisto->numOfEntries, 1);
+  int32_t idx = histoBinarySearch(pHisto->elems, pHisto->numOfEntries, 1);
   assert(idx == 1);
 
-  idx = vnodeHistobinarySearch(pHisto->elems, pHisto->numOfEntries, 9);
+  idx = histoBinarySearch(pHisto->elems, pHisto->numOfEntries, 9);
   assert(idx == 9);
 
-  idx = vnodeHistobinarySearch(pHisto->elems, pHisto->numOfEntries, 20);
+  idx = histoBinarySearch(pHisto->elems, pHisto->numOfEntries, 20);
   assert(idx == 10);
 
-  idx = vnodeHistobinarySearch(pHisto->elems, pHisto->numOfEntries, -1);
+  idx = histoBinarySearch(pHisto->elems, pHisto->numOfEntries, -1);
   assert(idx == 0);
 
-  idx = vnodeHistobinarySearch(pHisto->elems, pHisto->numOfEntries, 3.9);
+  idx = histoBinarySearch(pHisto->elems, pHisto->numOfEntries, 3.9);
   assert(idx == 4);
 
   free(pHisto);
diff --git a/src/tsdb/src/tsdbCommit.c b/src/tsdb/src/tsdbCommit.c
index 637b02cd32ae8ad8e4077684609dcac23922d8a0..6b2ffe118ebf4a7ab085c46d3c56b2f3e9d1d261 100644
--- a/src/tsdb/src/tsdbCommit.c
+++ b/src/tsdb/src/tsdbCommit.c
@@ -161,6 +161,11 @@ _err:
 
 static void tsdbEndCommit(STsdbRepo *pRepo, int eno) {
   if (pRepo->appH.notifyStatus) pRepo->appH.notifyStatus(pRepo->appH.appH, TSDB_STATUS_COMMIT_OVER, eno);
+  SMemTable *pIMem = pRepo->imem;
+  tsdbLockRepo(pRepo);
+  pRepo->imem = NULL;
+  tsdbUnlockRepo(pRepo);
+  tsdbUnRefMemTable(pRepo, pIMem);
   sem_post(&(pRepo->readyToCommit));
 }
 
diff --git a/src/tsdb/src/tsdbMemTable.c b/src/tsdb/src/tsdbMemTable.c
index 999e2deb413eb13cc7119ee9042a260366c5f9a3..bedefa55ed856402b2fdf92a3692a10397848ff3 100644
--- a/src/tsdb/src/tsdbMemTable.c
+++ b/src/tsdb/src/tsdbMemTable.c
@@ -17,6 +17,7 @@
 #include "tsdbMain.h"
 
 #define TSDB_DATA_SKIPLIST_LEVEL 5
+#define TSDB_MAX_INSERT_BATCH 512
 
 static SMemTable * tsdbNewMemTable(STsdbRepo *pRepo);
 static void        tsdbFreeMemTable(SMemTable *pMemTable);
@@ -205,7 +206,7 @@ void *tsdbAllocBytes(STsdbRepo *pRepo, int bytes) {
 int tsdbAsyncCommit(STsdbRepo *pRepo) {
   if (pRepo->mem == NULL) return 0;
 
-  SMemTable *pIMem = pRepo->imem;
+  ASSERT(pRepo->imem == NULL);
 
   sem_wait(&(pRepo->readyToCommit));
 
@@ -220,8 +221,6 @@ int tsdbAsyncCommit(STsdbRepo *pRepo) {
   tsdbScheduleCommit(pRepo);
   if (tsdbUnlockRepo(pRepo) < 0) return -1;
 
-  if (tsdbUnRefMemTable(pRepo, pIMem) < 0) return -1;
-
   return 0;
 }
 
@@ -606,19 +605,13 @@ static int tsdbInsertDataToTable(STsdbRepo *pRepo, SSubmitBlk *pBlock, int32_t *
   STable *       pTable = NULL;
   SSubmitBlkIter blkIter = {0};
   SDataRow       row = NULL;
-  void **        rows = NULL;
+  void *         rows[TSDB_MAX_INSERT_BATCH] = {0};
   int            rowCounter = 0;
 
   ASSERT(pBlock->tid < pMeta->maxTables);
   pTable = pMeta->tables[pBlock->tid];
   ASSERT(pTable != NULL && TABLE_UID(pTable) == pBlock->uid);
 
-  rows = (void **)calloc(pBlock->numOfRows, sizeof(void *));
-  if (rows == NULL) {
-    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
-    return -1;
-  }
-
   tsdbInitSubmitBlkIter(pBlock, &blkIter);
   while ((row = tsdbGetSubmitBlkNext(&blkIter)) != NULL) {
     if (tsdbCopyRowToMem(pRepo, row, pTable, &(rows[rowCounter])) < 0) {
@@ -632,9 +625,18 @@ static int tsdbInsertDataToTable(STsdbRepo *pRepo, SSubmitBlk *pBlock, int32_t *
     if (rows[rowCounter] != NULL) {
       rowCounter++;
     }
+
+    if (rowCounter == TSDB_MAX_INSERT_BATCH) {
+      if (tsdbInsertDataToTableImpl(pRepo, pTable, rows, rowCounter) < 0) {
+        goto _err;
+      }
+
+      rowCounter = 0;
+      memset(rows, 0, sizeof(rows));
+    }
   }
 
-  if (tsdbInsertDataToTableImpl(pRepo, pTable, rows, rowCounter) < 0) {
+  if (rowCounter > 0 && tsdbInsertDataToTableImpl(pRepo, pTable, rows, rowCounter) < 0) {
     goto _err;
   }
 
@@ -642,11 +644,9 @@ static int tsdbInsertDataToTable(STsdbRepo *pRepo, SSubmitBlk *pBlock, int32_t *
   pRepo->stat.pointsWritten += points * schemaNCols(pSchema);
   pRepo->stat.totalStorage += points * schemaVLen(pSchema);
 
-  free(rows);
   return 0;
 
 _err:
-  free(rows);
   return -1;
 }
 
diff --git a/tests/pytest/crash_gen/crash_gen_main.py b/tests/pytest/crash_gen/crash_gen_main.py
index e2ce4b26fa2fa8cc9c601218c1bf19d838b57c46..c6b857b097671b8faf650f4659c2b2990ef67d97 100755
--- a/tests/pytest/crash_gen/crash_gen_main.py
+++ b/tests/pytest/crash_gen/crash_gen_main.py
@@ -2224,22 +2224,25 @@ class ClientManager:
         if svcMgr: # gConfig.auto_start_service:
             svcMgr.stopTaosServices()
             svcMgr = None
-        # Print exec status, etc., AFTER showing messages from the server
-        self.conclude()
-        # print("TC failed (2) = {}".format(self.tc.isFailed()))
-        # Linux return code: ref https://shapeshed.com/unix-exit-codes/
-        ret = 1 if self.tc.isFailed() else 0
-        self.tc.cleanup()
+        
 
         # Release global variables
         gConfig = None
         gSvcMgr = None
         logger = None
+        
+        thPool = None
+        dbManager.cleanUp() # destructor wouldn't run in time
+        dbManager = None
 
+        # Print exec status, etc., AFTER showing messages from the server
+        self.conclude()
+        # print("TC failed (2) = {}".format(self.tc.isFailed()))
+        # Linux return code: ref https://shapeshed.com/unix-exit-codes/
+        ret = 1 if self.tc.isFailed() else 0
+        self.tc.cleanup()
         # Release variables here
         self.tc = None
-        thPool = None
-        dbManager = None
 
         gc.collect() # force garbage collection
         # h = hpy()
diff --git a/tests/pytest/crash_gen/db.py b/tests/pytest/crash_gen/db.py
index 855e18be55fd5ae0d88865644a2ebfc836b7ccf3..dc072d7abce68debd69cb162a4d784fcc5b68c4e 100644
--- a/tests/pytest/crash_gen/db.py
+++ b/tests/pytest/crash_gen/db.py
@@ -394,6 +394,7 @@ class DbManager():
             cType == 'native') else DbConn.createRest(dbTarget)
         try:
             self._dbConn.open()  # may throw taos.error.ProgrammingError: disconnected
+            Logging.debug("DbManager opened DB connection...")
         except taos.error.ProgrammingError as err:
             # print("Error type: {}, msg: {}, value: {}".format(type(err), err.msg, err))
             if (err.msg == 'client disconnected'):  # cannot open DB connection
@@ -412,6 +413,10 @@ class DbManager():
         # Moved to Database()
         # self._stateMachine = StateMechine(self._dbConn)
 
+    def __del__(self):
+        ''' Release the underlying DB connection upon deletion of DbManager '''
+        self.cleanUp()
+
     def getDbConn(self):
         return self._dbConn
 
@@ -438,5 +443,8 @@ class DbManager():
         return "table_{}".format(tblNum)
 
     def cleanUp(self):
-        self._dbConn.close()
+        if self._dbConn:
+            self._dbConn.close()
+            self._dbConn = None
+            Logging.debug("DbManager closed DB connection...")
 
diff --git a/tests/pytest/crash_gen/misc.py b/tests/pytest/crash_gen/misc.py
index a374ed943b41b52c2ccbee0825bca3080ed43ea9..6ea5691ce223eb1c14214d4b11c47cf85e29c795 100644
--- a/tests/pytest/crash_gen/misc.py
+++ b/tests/pytest/crash_gen/misc.py
@@ -2,6 +2,7 @@ import threading
 import random
 import logging
 import os
+import sys
 
 import taos
 
@@ -53,7 +54,7 @@ class Logging:
         # global misc.logger
         _logger = logging.getLogger('CrashGen')  # real logger
         _logger.addFilter(LoggingFilter())
-        ch = logging.StreamHandler()
+        ch = logging.StreamHandler(sys.stdout) # Ref: https://stackoverflow.com/questions/14058453/making-python-loggers-output-all-messages-to-stdout-in-addition-to-log-file
         _logger.addHandler(ch)
 
         # Logging adapter, to be used as a logger
diff --git a/tests/pytest/crash_gen_bootstrap.py b/tests/pytest/crash_gen_bootstrap.py
index fd12284b9d7782ac7df89c37fcb653ca3bebe82b..de2d9b0780f3654424d8e077a4dda9ac5ac0ed50 100644
--- a/tests/pytest/crash_gen_bootstrap.py
+++ b/tests/pytest/crash_gen_bootstrap.py
@@ -19,5 +19,5 @@ if __name__ == "__main__":
     mExec.init()
     exitCode = mExec.run()
 
-    print("Exiting with code: {}".format(exitCode))
+    print("\nCrash_Gen is now exiting with status code: {}".format(exitCode))
     sys.exit(exitCode)
diff --git a/tests/pytest/import_merge/importCacheFileH.py b/tests/pytest/import_merge/importCacheFileH.py
index 3398f7bdad8d7524e223f0a2847b579081686476..33724dfa6889903a34836844271f5843c7cb36e4 100644
--- a/tests/pytest/import_merge/importCacheFileH.py
+++ b/tests/pytest/import_merge/importCacheFileH.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importCacheFileHO.py b/tests/pytest/import_merge/importCacheFileHO.py
index 19520dc3d048a267c03850b608d47db20394c43d..9f552978f9bb5b0be72eb7cba7ebd073114e740b 100644
--- a/tests/pytest/import_merge/importCacheFileHO.py
+++ b/tests/pytest/import_merge/importCacheFileHO.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importCacheFileHPO.py b/tests/pytest/import_merge/importCacheFileHPO.py
index 9e0a57fb462cdb6ae1dee3c8bfee4488c99a76a0..f2d0a3ddbfb4c0a2a111aab423e32c0ed4683e47 100644
--- a/tests/pytest/import_merge/importCacheFileHPO.py
+++ b/tests/pytest/import_merge/importCacheFileHPO.py
@@ -57,7 +57,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importCacheFileS.py b/tests/pytest/import_merge/importCacheFileS.py
index 2f0af569e564b64cbb88c048762e8d41dcf21cbd..250952b2377f9d164c16801b6ead5f695d4f7c43 100644
--- a/tests/pytest/import_merge/importCacheFileS.py
+++ b/tests/pytest/import_merge/importCacheFileS.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importCacheFileSub.py b/tests/pytest/import_merge/importCacheFileSub.py
index 300bb6e8d09f4484e22e64a0f2caf50cab7c8ab4..663bdcd6351c02a91da309502e0a7f5ec9878086 100644
--- a/tests/pytest/import_merge/importCacheFileSub.py
+++ b/tests/pytest/import_merge/importCacheFileSub.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importCacheFileT.py b/tests/pytest/import_merge/importCacheFileT.py
index ab33cf6a93c4bbd7f27967f6a70b61fc62230f65..f2feeeacff11a4c8a2d65feaa08cd1b57264e0c9 100644
--- a/tests/pytest/import_merge/importCacheFileT.py
+++ b/tests/pytest/import_merge/importCacheFileT.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importCacheFileTO.py b/tests/pytest/import_merge/importCacheFileTO.py
index 00e22da976618b4ee870a5702542f669693e3727..421ca6a755425690e7ec76d9a932ce11a65cb141 100644
--- a/tests/pytest/import_merge/importCacheFileTO.py
+++ b/tests/pytest/import_merge/importCacheFileTO.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importCacheFileTPO.py b/tests/pytest/import_merge/importCacheFileTPO.py
index c6089e1d687fea6ac900931a8171e45f4923f0cb..ca582d7d5aad8106d7c3d12439001fda84d5004c 100644
--- a/tests/pytest/import_merge/importCacheFileTPO.py
+++ b/tests/pytest/import_merge/importCacheFileTPO.py
@@ -57,7 +57,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataH2.py b/tests/pytest/import_merge/importDataH2.py
index a21f0c47be2eb11a57182d22b56d4447ff2d7ab6..4de567d943a1fe843ec16dd4589054ebcef76488 100644
--- a/tests/pytest/import_merge/importDataH2.py
+++ b/tests/pytest/import_merge/importDataH2.py
@@ -59,7 +59,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataHO.py b/tests/pytest/import_merge/importDataHO.py
index fdcaedd83c99482914805cb65a067cbcbc78a128..f40de71d6d3967aac6d851deae2810aed63bc3c8 100644
--- a/tests/pytest/import_merge/importDataHO.py
+++ b/tests/pytest/import_merge/importDataHO.py
@@ -60,7 +60,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataHO2.py b/tests/pytest/import_merge/importDataHO2.py
index b094701132677d6e72e834b16b7edc106682be14..518975e0b727db0d51bd6f5b68e690356988e2fe 100644
--- a/tests/pytest/import_merge/importDataHO2.py
+++ b/tests/pytest/import_merge/importDataHO2.py
@@ -60,7 +60,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataHPO.py b/tests/pytest/import_merge/importDataHPO.py
index 9d74c0c3522eba3687618132c27ce95f86f91b91..c7f0625d4bf09de49066c9ea19d4936bdd00e811 100644
--- a/tests/pytest/import_merge/importDataHPO.py
+++ b/tests/pytest/import_merge/importDataHPO.py
@@ -62,7 +62,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataLastH.py b/tests/pytest/import_merge/importDataLastH.py
index c8e5f62423dc21254d215fac41926aeb9ce5ba40..f736cb925a405c8588d01faad0b08759127962b4 100644
--- a/tests/pytest/import_merge/importDataLastH.py
+++ b/tests/pytest/import_merge/importDataLastH.py
@@ -59,7 +59,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataLastHO.py b/tests/pytest/import_merge/importDataLastHO.py
index 33215997a4220b65228b630ebc350bf9dae15046..b1eebfdd47ed1fbb5185b7547927ea50a29bc64e 100644
--- a/tests/pytest/import_merge/importDataLastHO.py
+++ b/tests/pytest/import_merge/importDataLastHO.py
@@ -59,7 +59,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataLastHPO.py b/tests/pytest/import_merge/importDataLastHPO.py
index fa8542f35b8e9639db20dc2e1886fca36140e825..9aa8127f50799039ceaa48dee957cdb903b890f0 100644
--- a/tests/pytest/import_merge/importDataLastHPO.py
+++ b/tests/pytest/import_merge/importDataLastHPO.py
@@ -61,7 +61,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataLastS.py b/tests/pytest/import_merge/importDataLastS.py
index 2f595fef542955e616ef2e6ebcce7f23bce71d80..2c1559d2903a4fde104603bb2ad5945ea8eddd1e 100644
--- a/tests/pytest/import_merge/importDataLastS.py
+++ b/tests/pytest/import_merge/importDataLastS.py
@@ -59,7 +59,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataLastSub.py b/tests/pytest/import_merge/importDataLastSub.py
index bfcad2d252cccb2404b3989c474310e0a19afe2e..415d1fcba27921267832323e6c3177678a215c9b 100644
--- a/tests/pytest/import_merge/importDataLastSub.py
+++ b/tests/pytest/import_merge/importDataLastSub.py
@@ -32,7 +32,7 @@ class TDTestCase:
         tdDnodes.stop(1)
         tdDnodes.deploy(1)
         tdDnodes.start(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
 
         tdSql.execute('reset query cache')
         tdSql.execute('drop database if exists db')
@@ -60,9 +60,9 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
 
         tdLog.info("================= step5")
         tdLog.info("import 10 data totally repetitive")
diff --git a/tests/pytest/import_merge/importDataLastT.py b/tests/pytest/import_merge/importDataLastT.py
index 08e944eb6836a6f7f938639b40a6124f7bb64ec6..839320cc22352f1009d0d786aa58cf8827fc8ff6 100644
--- a/tests/pytest/import_merge/importDataLastT.py
+++ b/tests/pytest/import_merge/importDataLastT.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataLastTO.py b/tests/pytest/import_merge/importDataLastTO.py
index a82c0541414298accfdfb447c318ffafd88e5852..0c35519fcf76e7d2faab3a2cb2c4cc702fe93f0b 100644
--- a/tests/pytest/import_merge/importDataLastTO.py
+++ b/tests/pytest/import_merge/importDataLastTO.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataLastTPO.py b/tests/pytest/import_merge/importDataLastTPO.py
index ff75a1b2ae87891853fa93f0f49fff339cf6e488..c7864ae14d68a3ef8860125920b3286921f65356 100644
--- a/tests/pytest/import_merge/importDataLastTPO.py
+++ b/tests/pytest/import_merge/importDataLastTPO.py
@@ -57,7 +57,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataS.py b/tests/pytest/import_merge/importDataS.py
index 37627e8d6bcc8319805275525ef7874132e0da4d..f0d56a5016fe5b059e1b51719b799d801219c2ca 100644
--- a/tests/pytest/import_merge/importDataS.py
+++ b/tests/pytest/import_merge/importDataS.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataSub.py b/tests/pytest/import_merge/importDataSub.py
index 17e2b141b7014fd2ce4d31f8c335e122aca730ba..1643cc89155507be6c5fa2c072755a8439b21aab 100644
--- a/tests/pytest/import_merge/importDataSub.py
+++ b/tests/pytest/import_merge/importDataSub.py
@@ -60,7 +60,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataT.py b/tests/pytest/import_merge/importDataT.py
index b0b7b82b790e81c475c714ba570a9a6f1801cc13..c23ad9a60533d94d34d11c70ea2743a1b8ab5c01 100644
--- a/tests/pytest/import_merge/importDataT.py
+++ b/tests/pytest/import_merge/importDataT.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataTO.py b/tests/pytest/import_merge/importDataTO.py
index c0b57136af7a51c1d184eb5789d95efc0148118c..b4c0d1a8adb6d4a3751d5a4a6547d0d03eab793b 100644
--- a/tests/pytest/import_merge/importDataTO.py
+++ b/tests/pytest/import_merge/importDataTO.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importDataTPO.py b/tests/pytest/import_merge/importDataTPO.py
index 8a1c9264b433484e768cdfffbccdb0966e3d15cd..38e8cfe9096135f1f9301d89bc8c6269d045e78f 100644
--- a/tests/pytest/import_merge/importDataTPO.py
+++ b/tests/pytest/import_merge/importDataTPO.py
@@ -57,9 +57,9 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
 
         tdLog.info("================= step5")
         tdLog.info("import 20 data later with partly overlap")
diff --git a/tests/pytest/import_merge/importHORestart.py b/tests/pytest/import_merge/importHORestart.py
index f74c4c76d616753f8cadc87ba715e473eae0fb46..05b5b42afff14c695690b7651bd385ee78f3bafb 100644
--- a/tests/pytest/import_merge/importHORestart.py
+++ b/tests/pytest/import_merge/importHORestart.py
@@ -57,7 +57,7 @@ class TDTestCase:
         tdLog.info("================= step5")
         tdDnodes.forcestop(1)
         tdDnodes.start(1)
-        tdLog.sleep(10)
+        #tdLog.sleep(10)
 
         tdLog.info("================= step6")
         tdSql.query('select * from tb1')
diff --git a/tests/pytest/import_merge/importHPORestart.py b/tests/pytest/import_merge/importHPORestart.py
index e5f79fbe6c2eb686d63f5b7de81651a98072a986..f9167709130d67b2909d3e9efd1acc482638836d 100644
--- a/tests/pytest/import_merge/importHPORestart.py
+++ b/tests/pytest/import_merge/importHPORestart.py
@@ -62,7 +62,7 @@ class TDTestCase:
         tdLog.info("================= step5")
         tdDnodes.forcestop(1)
         tdDnodes.start(1)
-        tdLog.sleep(10)
+        #tdLog.sleep(10)
 
         tdLog.info("================= step6")
         tdSql.query('select * from tb1')
diff --git a/tests/pytest/import_merge/importHRestart.py b/tests/pytest/import_merge/importHRestart.py
index be67039789dd660ddb0be8d56753737010e47e79..c1d50378b20a11b4d562b408d7bec07364969d19 100644
--- a/tests/pytest/import_merge/importHRestart.py
+++ b/tests/pytest/import_merge/importHRestart.py
@@ -54,7 +54,7 @@ class TDTestCase:
         tdLog.info("================= step5")
         tdDnodes.forcestop(1)
         tdDnodes.start(1)
-        tdLog.sleep(10)
+        #tdLog.sleep(10)
 
         tdLog.info("================= step6")
         tdSql.query('select * from tb1')
diff --git a/tests/pytest/import_merge/importInsertThenImport.py b/tests/pytest/import_merge/importInsertThenImport.py
index 292fae8c47b398dcbacdb8b76592826bcc8b6019..1372177de36c1f67ab85ba4a63c26553ee4a7de4 100644
--- a/tests/pytest/import_merge/importInsertThenImport.py
+++ b/tests/pytest/import_merge/importInsertThenImport.py
@@ -61,7 +61,7 @@ class TDTestCase:
         tdLog.info("================= step5")
         tdDnodes.stop(1)
         tdDnodes.start(1)
-        tdLog.sleep(10)
+        #tdLog.sleep(10)
 
         tdLog.info("================= step6")
         tdLog.info("import 100 sequential data again")
diff --git a/tests/pytest/import_merge/importLastH.py b/tests/pytest/import_merge/importLastH.py
index 17fa233e3723e1d9e6cc4ec97c8eac2716751f00..2887c71e040b7ea89e42da69e597bcb843a2df5c 100644
--- a/tests/pytest/import_merge/importLastH.py
+++ b/tests/pytest/import_merge/importLastH.py
@@ -53,7 +53,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importLastHO.py b/tests/pytest/import_merge/importLastHO.py
index adb44fc0eab9a4923b0896a1357b24603f1ff3fd..1681212b6b8c5d002e6f3d2b5853534382bb4d10 100644
--- a/tests/pytest/import_merge/importLastHO.py
+++ b/tests/pytest/import_merge/importLastHO.py
@@ -53,7 +53,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importLastHPO.py b/tests/pytest/import_merge/importLastHPO.py
index d8ed2d9ef10dbaa52e92ba50625be25c495091ea..389b3c11ed04b0359564a41c7b383e37e9bcabdd 100644
--- a/tests/pytest/import_merge/importLastHPO.py
+++ b/tests/pytest/import_merge/importLastHPO.py
@@ -55,7 +55,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importLastS.py b/tests/pytest/import_merge/importLastS.py
index bf222a0d5f3c27c5c7774b384799a6a0aa5e4114..e6393bbfae2f41efd1ff740f4e542715f23f8adf 100644
--- a/tests/pytest/import_merge/importLastS.py
+++ b/tests/pytest/import_merge/importLastS.py
@@ -53,7 +53,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importLastSub.py b/tests/pytest/import_merge/importLastSub.py
index 5a6b9f41502970149257b1aef5c7a37824401768..4ff6cf27bdf582040360e40ce13d28df7dfc8949 100644
--- a/tests/pytest/import_merge/importLastSub.py
+++ b/tests/pytest/import_merge/importLastSub.py
@@ -53,7 +53,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importLastT.py b/tests/pytest/import_merge/importLastT.py
index 2b1be1fe2b37aa5e4d59bb6ecef7d0bb2180cf9d..145b1bd69097804728020ea1b3b8a0ccf7e86d27 100644
--- a/tests/pytest/import_merge/importLastT.py
+++ b/tests/pytest/import_merge/importLastT.py
@@ -57,7 +57,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importLastTO.py b/tests/pytest/import_merge/importLastTO.py
index ce189f63718956991982bd33296eb71bd5a82d45..a159dac4acea9c1c278025e157ff3fe09487e858 100644
--- a/tests/pytest/import_merge/importLastTO.py
+++ b/tests/pytest/import_merge/importLastTO.py
@@ -57,7 +57,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importLastTPO.py b/tests/pytest/import_merge/importLastTPO.py
index 627d090855ac320f56a90fb647101e8ccc315acd..453b922a68bc7a051aa60d51943ffb759444ee5b 100644
--- a/tests/pytest/import_merge/importLastTPO.py
+++ b/tests/pytest/import_merge/importLastTPO.py
@@ -59,7 +59,7 @@ class TDTestCase:
 
         tdLog.info("================= step4")
         tdDnodes.stop(1)
-        tdLog.sleep(5)
+        #tdLog.sleep(5)
         tdDnodes.start(1)
 
         tdLog.info("================= step5")
diff --git a/tests/pytest/import_merge/importSRestart.py b/tests/pytest/import_merge/importSRestart.py
index 29f5a19b54fb0cbf1eb81a66c66813f3fcdd9982..58f0f60e0af0660e4550966c2f0b1741aefbc33c 100644
--- a/tests/pytest/import_merge/importSRestart.py
+++ b/tests/pytest/import_merge/importSRestart.py
@@ -64,7 +64,7 @@ class TDTestCase:
         tdLog.info("================= step5")
         tdDnodes.forcestop(1)
         tdDnodes.start(1)
-        tdLog.sleep(10)
+        #tdLog.sleep(10)
 
         tdLog.info("================= step6")
         tdSql.query('select * from tb1')
diff --git a/tests/pytest/import_merge/importSubRestart.py b/tests/pytest/import_merge/importSubRestart.py
index b1a6f30c436c5aa52d5ee4affa03d18c5475ced7..85594e1772409f7c24a5d2ce8aa25b6ba7567a5d 100644
--- a/tests/pytest/import_merge/importSubRestart.py
+++ b/tests/pytest/import_merge/importSubRestart.py
@@ -64,7 +64,7 @@ class TDTestCase:
         tdLog.info("================= step5")
         tdDnodes.forcestop(1)
         tdDnodes.start(1)
-        tdLog.sleep(10)
+        #tdLog.sleep(10)
 
         tdLog.info("================= step6")
         tdSql.query('select * from tb1')
diff --git a/tests/pytest/import_merge/importTORestart.py b/tests/pytest/import_merge/importTORestart.py
index 07eb6c28cb79c16504f2acab036a3b66c3bccabf..10ac77d759192de329ab0818b79610259d05b7d7 100644
--- a/tests/pytest/import_merge/importTORestart.py
+++ b/tests/pytest/import_merge/importTORestart.py
@@ -64,7 +64,7 @@ class TDTestCase:
         tdLog.info("================= step5")
         tdDnodes.forcestop(1)
         tdDnodes.start(1)
-        tdLog.sleep(10)
+        #tdLog.sleep(10)
 
         tdLog.info("================= step6")
         tdSql.query('select * from tb1')
diff --git a/tests/pytest/import_merge/importTPORestart.py b/tests/pytest/import_merge/importTPORestart.py
index 10bbf3efced90b6c255326c0e8b8e0c106a3a038..ab86a0247f179bd6dab397a069ca9b4aaf4da61f 100644
--- a/tests/pytest/import_merge/importTPORestart.py
+++ b/tests/pytest/import_merge/importTPORestart.py
@@ -68,7 +68,7 @@ class TDTestCase:
         tdLog.info("================= step5")
         tdDnodes.forcestop(1)
         tdDnodes.start(1)
-        tdLog.sleep(10)
+        #tdLog.sleep(10)
 
         tdLog.info("================= step6")
         tdSql.query('select * from tb1')
diff --git a/tests/pytest/import_merge/importTRestart.py b/tests/pytest/import_merge/importTRestart.py
index 63a9368eca2b6a3377b32dc6a3948cf5a0ba1186..6106bdd75310369d53ce8148f937655301b64c12 100644
--- a/tests/pytest/import_merge/importTRestart.py
+++ b/tests/pytest/import_merge/importTRestart.py
@@ -61,7 +61,7 @@ class TDTestCase:
         tdLog.info("================= step5")
         tdDnodes.forcestop(1)
         tdDnodes.start(1)
-        tdLog.sleep(10)
+        #tdLog.sleep(10)
 
         tdLog.info("================= step6")
         tdSql.query('select * from tb1')
diff --git a/tests/pytest/query/query.py b/tests/pytest/query/query.py
index da0ef96d0efde77b716ded06cc7efaa96ea3bb7b..87635f86f39fb317907f689307eeefa9f3aef124 100644
--- a/tests/pytest/query/query.py
+++ b/tests/pytest/query/query.py
@@ -16,7 +16,7 @@ import taos
 from util.log import tdLog
 from util.cases import tdCases
 from util.sql import tdSql
-
+from util.dnodes import tdDnodes
 
 class TDTestCase:
     def init(self, conn, logSql):
@@ -44,6 +44,25 @@ class TDTestCase:
         tdSql.query("select * from db.st where ts='2020-05-13 10:00:00.000'")
         tdSql.checkRows(1)
 
+        ## test case for https://jira.taosdata.com:18080/browse/TD-2488
+        tdSql.execute("create table m1(ts timestamp, k int) tags(a int)")
+        tdSql.execute("create table t1 using m1 tags(1)")
+        tdSql.execute("create table t2 using m1 tags(2)")
+        tdSql.execute("insert into t1 values('2020-1-1 1:1:1', 1)")
+        tdSql.execute("insert into t1 values('2020-1-1 1:10:1', 2)")
+        tdSql.execute("insert into t2 values('2020-1-1 1:5:1', 99)")
+        
+        tdSql.query("select count(*) from m1 where ts = '2020-1-1 1:5:1' ")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
+        tdDnodes.stop(1)
+        tdDnodes.start(1)
+
+        tdSql.query("select count(*) from m1 where ts = '2020-1-1 1:5:1' ")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
     def stop(self):
         tdSql.close()
         tdLog.success("%s successfully executed" % __file__)