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 Hi, (I sent this previously without a subject line. ) I am using MPICH 4. 2. 2 on Ubuntu 24. 04 testing with the small program cpi that calculates the value of pi using MPI. I can start on host1 to run cpi on either host1 or host2 alone and I can
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<div dir="ltr"><div>Hi,</div><div><br></div><div>(I sent this previously without a subject line.)</div><div><br></div><div><span style="color:rgb(12,13,14);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI Adjusted","Segoe UI","Liberation Sans",sans-serif;font-size:15px">I am using MPICH 4.2.2 on Ubuntu 24.04 testing with the small program cpi that calculates the value of pi using MPI. I can start on host1 to run cpi on either host1 or host2 alone and I can start on host2 to run cpi on either host2 or host1 alone. The problem occurs only if I try to use both host1 and host2 together.</span><br></div><div><span style="color:rgb(12,13,14);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI Adjusted","Segoe UI","Liberation Sans",sans-serif;font-size:15px"><br></span></div><div><p style="margin:0px 0px 1.1em;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-variant-alternates:inherit;font-stretch:inherit;line-height:inherit;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI Adjusted","Segoe UI","Liberation Sans",sans-serif;font-kerning:inherit;font-feature-settings:inherit;font-size:15px;vertical-align:baseline;box-sizing:inherit;clear:both;color:rgb(12,13,14)">This is done using, for example, the command<br style="box-sizing:inherit"><em style="margin:0px;padding:0px;border:0px;font-variant:inherit;font-weight:inherit;font-stretch:inherit;line-height:inherit;font-family:inherit;font-kerning:inherit;font-feature-settings:inherit;vertical-align:baseline;box-sizing:inherit">mpiexec -host host1,host2 -n 2 cpi</em><br style="box-sizing:inherit">then it ends with the error</p><p style="margin:0px 0px 1.1em;padding:0px;border:0px;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-variant-alternates:inherit;font-stretch:inherit;line-height:inherit;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI Adjusted","Segoe UI","Liberation Sans",sans-serif;font-kerning:inherit;font-feature-settings:inherit;font-size:15px;vertical-align:baseline;box-sizing:inherit;clear:both;color:rgb(12,13,14)">Abort(77718927) on node 1: Fatal error in internal_Init: Other MPI error, error stack:<br style="box-sizing:inherit">internal_Init(48306).............: MPI_Init(argc=0x7ffdb68e7fec, argv=0x7ffdb68e7fe0) failed<br style="box-sizing:inherit">MPII_Init_thread(265)............:<br style="box-sizing:inherit">MPIR_init_comm_world(34).........:<br style="box-sizing:inherit">MPIR_Comm_commit(823)............:<br style="box-sizing:inherit">MPID_Comm_commit_post_hook(222)..:<br style="box-sizing:inherit">MPIDI_world_post_init(660).......:<br style="box-sizing:inherit">MPIDI_OFI_init_vcis(842).........:<br style="box-sizing:inherit">check_num_nics(891)..............:<br style="box-sizing:inherit">MPIR_Allreduce_allcomm_auto(4726):<br style="box-sizing:inherit">MPIC_Sendrecv(306)...............:<br style="box-sizing:inherit">MPIC_Wait(91)....................:<br style="box-sizing:inherit">MPIR_Wait(780)...................:<br style="box-sizing:inherit">MPIR_Wait_state(737).............:<br style="box-sizing:inherit">MPIDI_progress_test(134).........:<br style="box-sizing:inherit">MPIDI_OFI_handle_cq_error(791)...: OFI poll failed (ofi_events.c:793:MPIDI_OFI_handle_cq_error:Input/output error) Abort(77718927) on node 0: Fatal error in internal_Init: Other MPI error, error stack:<br style="box-sizing:inherit">internal_Init(48306).............: MPI_Init(argc=0x7ffcb5b28adc, argv=0x7ffcb5b28ad0) failed<br style="box-sizing:inherit">MPII_Init_thread(265)............:<br style="box-sizing:inherit">MPIR_init_comm_world(34).........:<br style="box-sizing:inherit">MPIR_Comm_commit(823)............:<br style="box-sizing:inherit">MPID_Comm_commit_post_hook(222)..:<br style="box-sizing:inherit">MPIDI_world_post_init(660).......:<br style="box-sizing:inherit">MPIDI_OFI_init_vcis(842).........:<br style="box-sizing:inherit">check_num_nics(891)..............:<br style="box-sizing:inherit">MPIR_Allreduce_allcomm_auto(4726):<br style="box-sizing:inherit">MPIC_Sendrecv(306)...............:<br style="box-sizing:inherit">MPIC_Wait(91)....................:<br style="box-sizing:inherit">MPIR_Wait(780)...................:<br style="box-sizing:inherit">MPIR_Wait_state(737).............:<br style="box-sizing:inherit">MPIDI_progress_test(134).........:<br style="box-sizing:inherit">MPIDI_OFI_handle_cq_error(791)...: OFI poll failed (ofi_events.c:793:MPIDI_OFI_handle_cq_error:Input/output error)</p>I searched through the archive of this mailing list and there is only one thread that has this OFI poll failed error. </div><div>In the thread, it mentioned this has something to do with the device configuration of ch4:ofi ?</div><div>I checked my configure log and it has </div><div>device : ch4:ofi (embedded libfabric) </div><div>in the configuration when I built the MPI. So I am wondering if I should switch this option to something else? If this will fix it. I am not too sure what other option I could substitute for ch4:ofi.</div><div><br></div><div>*****************************************************</div><div><br></div><div>Next I tried running configure for a build with the --enable-device = ch3:nemesis option. </div><div>Now again I can run the cpi on any  of host1 or host2 alone. If I run it on host1 and host2 together, it just crashed with a core dump.</div><div><br></div><div>Using the --enable-device = ch3:sock configure option resulted in more or less the same problem but now it just quits silently when running on host1 and host2 together.</div><div><br></div><div>Any ideas?</div><div>Thanks!</div><font color="#888888"><div>Stephen.</div><div><br></div></font></div>