Fix a bug that MPP tasks may leak threads forever (pingcap#4241)

close pingcap#4238
JaySon-Huang · Mar 17, 2022 · d647dfd · d647dfd
1 parent 4662376
commit d647dfd
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/dbms/src/Flash/Mpp/MPPTunnel.cpp b/dbms/src/Flash/Mpp/MPPTunnel.cpp
@@ -217,7 +217,9 @@ void MPPTunnelBase<Writer>::connect(Writer * writer_)
     {
         std::unique_lock lk(mu);
         if (connected)
-            throw Exception("has connected");
+            throw Exception("MPPTunnel has connected");
+        if (finished)
+            throw Exception("MPPTunnel has finished");
 
         LOG_TRACE(log, "ready to connect");
         if (is_local)