<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class="">Greetings,</div><div class=""><br class=""></div><div class="">when running an application (atmospheric science) with MPICH on an AWS ARM (not x86) instance (with Linux Ubuntu Server 20.04),</div><div class="">our process crashes at the end of the processing.</div><div class=""><br class=""></div><div class="">MPICH was installed precompiled with the Ubuntu apt provisioning tool:</div><div class=""><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">$ sudo apt install -y mpich</span></div></div><div class=""><br class=""></div><div class=""><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">$ apt list</span></div></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[only relevant lines displayed for brevity]</span></div><div class=""><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">lib</span><span style="font-variant-ligatures: no-common-ligatures; color: #b42419" class=""><b class="">mpich</b></span><span style="font-variant-ligatures: no-common-ligatures" class="">-dev/focal,now 3.3.2-2build1 arm64 [residual-config]</span></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">lib</span><span style="font-variant-ligatures: no-common-ligatures; color: #b42419" class=""><b class="">mpich</b></span><span style="font-variant-ligatures: no-common-ligatures" class="">12/focal,now 3.3.2-2build1 arm64 [installed,auto-removable]</span></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures; color: #b42419" class=""><b class="">mpich</b></span><span style="font-variant-ligatures: no-common-ligatures" class="">-doc/focal 3.3.2-2build1 all</span></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures; color: #b42419" class=""><b class="">mpich</b></span><span style="font-variant-ligatures: no-common-ligatures" class="">/focal 3.3.2-2build1 arm64</span></div></div><div class=""><br class=""></div><div class="">Luckily, we got some debug information in <font face="Menlo" style="font-size: 11px;" class="">mpid</font> that can be valuable:</div><div class=""><br class=""></div><div class=""><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">Assertion failed in file src/mpid/ch3/channels/nemesis/src/ch3_progress.c at line 530: payload_len >= sizeof (MPIDI_CH3_Pkt_t)</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">0xffff86833f5f ???</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-tab-span" style="white-space: pre;"> </span>???:0</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">0xffff86881eef ???</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-tab-span" style="white-space: pre;"> </span>???:0</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">0xffff8683793f ???</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-tab-span" style="white-space: pre;"> </span>???:0</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">0xffff8686c543 ???</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-tab-span" style="white-space: pre;"> </span>???:0</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">0xffff8676d4b3 ???</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-tab-span" style="white-space: pre;"> </span>???:0</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">0xffff8637e6eb ???</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-tab-span" style="white-space: pre;"> </span>???:0</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">0xffff8637e85b ???</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-tab-span" style="white-space: pre;"> </span>???:0</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">0xffff86369093 ???</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-tab-span" style="white-space: pre;"> </span>???:0</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">0xaaaac5491e6f ???</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-tab-span" style="white-space: pre;"> </span>???:0</span></div><div class="" style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">internal ABORT - process 22</span></div></div><div class=""><br class=""></div><div class="">The same application has been used for years with several MPI implementations (MPICH, OpenMPI, Intel MPI) on x86 systems without problem.</div><div class=""><br class=""></div><div class="">It was successfully tested with MPICH on Linux Ubuntu Server 20.04 x86 shortly alongside the ARM test.</div><div class="">We also tested the application with another MPI implementation (namely, OpenMPI) on the same ARM instance and it did work.</div><div class=""><br class=""></div><div class="">We are perfectly fine using another MPI implementation in this specific case, but we thought that this issue would be of some interest to the MPICH maintenance team.</div><div class=""><br class=""></div><div class="">Best regards</div><br class=""><div class="">
<div>Fabrice Ducos</div><div>Ingénieur d’études CNRS</div><div>Laboratoire d’Optique Atmosphérique - UMR CNRS 8518</div><div><br class=""></div><div>Faculté des Sciences et Technologies</div><div>Bâtiment P5 - Bureau 325</div><div>Université de Lille - Cité Scientifique</div><div>59655 Villeneuve d’Ascq</div><div><br class=""></div><br class="Apple-interchange-newline">
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