Created attachment 1472 [details]
client.cpp

TAO VERSION: 1.2.1
     ACE VERSION: 6.2.1

     HOST MACHINE and OPERATING SYSTEM:
        Linux debian 6.0 on amd64

     COMPILER NAME AND VERSION: g++-4.4.5

     $ACE_ROOT/ace/config.h FILE: config-linux.h

     THE $ACE_ROOT/include/makeinclude/platform_macros.GNU FILE:
        platform-linux.GNU

     CONTENTS OF $ACE_ROOT/bin/MakeProjectCreator/config/default.features:
       unmidified

     AREA/CLASS/EXAMPLE AFFECTED: LF_Strategy

     DOES THE PROBLEM AFFECT:
         EXECUTION: Yes

     SYNOPSIS:
In 2 threaded application, we experience intermittent CORBA::TIMEOUT 
exceptions from a thread invoking RPC call, while other thread is busy.

     DESCRIPTION:
I have 2 threads, both of them running orb->run() in TP_Reactor. Main 
task of the application is executing every 5 minutes, and it run by a 
timer. Application runs client RPC every 1 minute to another CORBA 
server, which normally returns immediately. Before invoking RPC, this 
thread invokes set_upcall_thread(). What I am seeing is that this RPC 
throws CORBA::TIMEOUT. It does not appear that remote CORBA server is 
busy at this time.

Here is code layout:

int Obj1::handle_timeout (...)
{
      // very long op, perhaps 2minutes (1)
      ACE_OS::sleep (20);
}

int Obj2::handle_timeout (...)
{
    try {
      remote->ping();
    } catch (CORBA::TIMEOUT&) {
       // the RPC comes back with TIMEOUT
    }
}

It appears that the thread which executes RPC is not capable of handling the response.

If I put this line after comment (1)
orb->orb_core()->lf_strategy().set_upcall_thread (
	orb->orb_core()->leader_follower());

I get the expected behavior - if server is up, I get response, if not, I get immediate CORBA::TRANSIENT

Attached is the sample code exposing the problem