diff --git a/src/wal/src/walMain.c b/src/wal/src/walMain.c
index e079653ab3696af73e187b3364d9ab00305cdb47..ae4beabb37955be4104895a330e27230598e82ef 100644
--- a/src/wal/src/walMain.c
+++ b/src/wal/src/walMain.c
@@ -196,6 +196,7 @@ void walFsync(void *handle) {
   if (pWal == NULL) return;
 
   if (pWal->level == TAOS_WAL_FSYNC && pWal->fd >=0) {
+    printf("WAL-SYNC executed\n");
     if (fsync(pWal->fd) < 0) {
       wError("wal:%s, fsync failed(%s)", pWal->name, strerror(errno));
     }
diff --git a/tests/pytest/crash_gen.py b/tests/pytest/crash_gen.py
index 9d3c66b97f12aea7e8685a923f26599d378ac8a5..a6e24142629542e6a0cbf39d22e715525e004b13 100755
--- a/tests/pytest/crash_gen.py
+++ b/tests/pytest/crash_gen.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python3.7
+#-----!/usr/bin/python3.7
 ###################################################################
 #           Copyright (c) 2016 by TAOS Technologies, Inc.
 #                     All rights reserved.
@@ -25,6 +25,7 @@ if sys.version_info[0] < 3:
 import getopt
 import argparse
 import copy
+import requests
 
 import threading
 import random
@@ -1061,8 +1062,11 @@ class DbManager():
 
     def getNextTick(self):
         with self._lock: # prevent duplicate tick
-            self._lastTick += datetime.timedelta(0, 1) # add one second to it
-            return self._lastTick
+            if Dice.throw(10) == 0 : # 1 in 10 chance
+                return self._lastTick + datetime.timedelta(0, -100)
+            else: # regular
+                self._lastTick += datetime.timedelta(0, 1) # add one second to it
+                return self._lastTick
 
     def getNextInt(self):
         with self._lock:
@@ -1220,7 +1224,12 @@ class Task():
                     # sys.exit(-1)
                     self._err = err
                     self._aborted = True
-        except:
+        except Exception as e :
+            self.logInfo("Non-TAOS exception encountered")
+            self._err = e 
+            self._aborted = True
+            traceback.print_exc()
+        except :
             self.logDebug("[=] Unexpected exception, SQL: {}".format(self._lastSql))
             raise
         self._execStats.endTaskType(self.__class__.__name__, self.isSuccess())
@@ -1699,6 +1708,8 @@ class ClientManager:
         dbc = dbManager.getDbConn()
         if dbc.query("show databases") == 0 : # no databae
             return
+        if dbc.query("show tables") == 0 : # no tables
+            return
 
         dbc.execute("use db")
         sTbName = dbManager.getFixedSuperTableName()        
diff --git a/tests/pytest/crash_gen.sh b/tests/pytest/crash_gen.sh
index c845b3976473bedc0fef5684c29b06f866df0840..de80361aa3ca655e81f5e36d511a6104e1c96aa6 100755
--- a/tests/pytest/crash_gen.sh
+++ b/tests/pytest/crash_gen.sh
@@ -38,4 +38,4 @@ export PYTHONPATH=$(pwd)/../../src/connector/python/linux/python3
 export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$(pwd)/../../build/build/lib
 
 # Now we are all let, and let's see if we can find a crash. Note we pass all params
-./crash_gen.py $@
+python3 ./crash_gen.py $@