diff --git a/cpp/dbpool.cc b/cpp/dbpool.cc
index 1c9690e..254173f 100644
--- a/cpp/dbpool.cc
+++ b/cpp/dbpool.cc
@@ -348,12 +348,6 @@ namespace f8
             }
         }
 
-        AsyncQueryRequest* GetAsyncQueryRequest(long long seqid)
-        {
-            auto itr = async_query_hash.find(seqid);
-            return itr != async_query_hash.end() ? itr->second : nullptr;
-        }
-
         void AsyncSqlOnOk(long long seqid, DataSet* data_set)
         {
             AsyncQueryRequest* request = GetAsyncQueryRequest(seqid);
@@ -418,15 +412,26 @@ namespace f8
             }
             a8::Timer::Instance()->AddDeadLineTimerAndAttach(1000 * 10,
                                                              a8::XParams()
-                                                             .SetSender(this)
-                                                             .SetParam1(p->context_id),
+                                                             .SetSender(p->context_id)
+                                                             .SetParam1(exec_async_query_msgid),
                                                              [] (const a8::XParams& param)
                                                              {
-
+                                                                 MsgQueue::Instance()->PostMsg_r(param.param1,
+                                                                                                 a8::XParams()
+                                                                                                 .SetSender(param.sender)
+                                                                                                 .SetParam1(AQE_CONN_ERROR));
                                                              },
                                                              &p->timer_attacher.timer_list_);
         }
 
+    private:
+
+        AsyncQueryRequest* GetAsyncQueryRequest(long long seqid)
+        {
+            auto itr = async_query_hash.find(seqid);
+            return itr != async_query_hash.end() ? itr->second : nullptr;
+        }
+
         DBThread* GetDBThread(long long hash_code)
         {
             if (db_thread_pool.empty() || hash_code < 0) {
@@ -436,10 +441,12 @@ namespace f8
         }
 
     public:
+        unsigned short exec_async_query_msgid = 0;
+
+    private:
         long long curr_seqid = 0;
         std::map<long long, AsyncQueryRequest*> async_query_hash;
 
-        unsigned short exec_async_query_msgid = 0;
         std::vector<DBThread*> db_thread_pool;
     };
 
@@ -486,4 +493,5 @@ namespace f8
     {
         impl_->InternalExecAsyncSql(1, conn_info, querystr, args, param, on_ok, on_error, hash_code);
     }
+
 }