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<div>First of all, MPI functions are not signal safe. So, if you try to use signals within your MPI program, things might break.</div>
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<div>— Sangmin</div>
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<div>On Oct 9, 2014, at 7:37 AM, Roy, Hirak <<a href="mailto:Hirak_Roy@mentor.com">Hirak_Roy@mentor.com</a>> wrote:</div>
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Hi ,<o:p></o:p></div>
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<o:p> </o:p></div>
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I have two MPI processes (server and client) launched independently by two different mpiexec command. (mpich-3.0.4, sock-device)<o:p></o:p></div>
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<span>1><span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-family: 'Times New Roman';"> <span class="Apple-converted-space"> </span></span></span>mpiexec –disable-auto-cleanup –n 1 ./server<o:p></o:p></div>
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<span>2><span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-family: 'Times New Roman';"> <span class="Apple-converted-space"> </span></span></span>mpiexec –disable-auto-cleanup –n 1 ./client<o:p></o:p></div>
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<o:p> </o:p></div>
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The server opens a port and does MPI_Comm_accept.<o:p></o:p></div>
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The client gets the port information and does MPI_Comm_connect and hence we get a new intercommunicator.<o:p></o:p></div>
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I don’t do MPI_Comm_merge.<o:p></o:p></div>
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<o:p> </o:p></div>
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I have installed my own signal handler for SIGUSR1 before even I call MPI_Init ( I guess, this will automatically chain the signal handler).<o:p></o:p></div>
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<o:p> </o:p></div>
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>> signal (SIGUSR1, mysignalhandler);<o:p></o:p></div>
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<o:p> </o:p></div>
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Now suppose, the<span class="Apple-converted-space"> </span><i>‘client’</i><span class="Apple-converted-space"> </span>process gets killed ( I forcefully kill the process by signal 9), I thought I would get SIGUSR1 in the process ‘<i>server’.<o:p></o:p></i></div>
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However, I don’t get any signal in ‘server’ process.<o:p></o:p></div>
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Am I doing something wrong?<o:p></o:p></div>
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I have noticed that if I start 4 client processes with single mpiexec command, and one client gets killed, rest of the 3 clients receive SIGUSR1.<o:p></o:p></div>
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<o:p> </o:p></div>
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Does this mean, SIGUSR1 is not forwarded across processes connected using inter-communicator?<o:p></o:p></div>
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<o:p> </o:p></div>
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<o:p> </o:p></div>
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Thanks,<o:p></o:p></div>
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Hirak<o:p></o:p></div>
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