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<p class="MsoNormal"><span style="color:#1F497D">Hi All,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">I am working on a MPI based server-client application.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">The number of clients are not fixed.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">The clients can come up at any time and will connect to server.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">The server runs two threads.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Thread 1: opens a port, calls MPI_Comm_accept on a loop on MPI_COMM_SELF.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Thread 2: Distributes works among the clients.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">When the client comes up, it calls MPI_Comm_connect to server.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">The problem I am facing is : how to terminate the blocking MPI_Comm_accept of Therad 1, once Thread2 is done with all the work?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">I tried the following thing which might not be legal to do:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Thread2 calls MPI_Comm_connect (MPI_COMM_SELF) to Thread1’s port. (created a new inter-communicator newComm)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">However, when I tried to send a non-blocking message to close the port from Thread2 (MPI_Isend, MPI_Wait) to Thread1 (MPI_Irecv, MPI_Wait) using newComm, the two threads wait forever.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Any help regarding the termination of MPI_Comm_accept will be appreciated.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Hirak<o:p></o:p></span></p>
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