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OFFICIAL<br>
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Hi all,</div>
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Recently I had a strange problem running DIFX . It ran OK but I got a lot of output along the lines of:</div>
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<span style="font-family: "Andale Mono", Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(18, 18, 18); background-color: rgb(255, 255, 255); font-weight: 430;">[HOSTNAME:PID] Read -1, expected 530112, errno = 1</span></p>
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This turned out to be a conflict between the default Debian security settings and MPI trying to figure out optimal setup.</div>
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Without understanding the security implications, I disabled via setting</div>
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<pre><div class="code-block__code !my-0 !rounded-lg !text-sm !leading-relaxed p-3.5" style="text-align: left; text-indent: 0px; text-transform: none; margin-left: 40px; font-family: "Andale Mono", Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(20, 24, 31);"><code style="font-family: "Andale Mono", Arial, Helvetica, sans-serif;">btl_vader_single_copy_mechanism = none</code></div></pre>
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In <span style="font-family: "Andale Mono", Arial, Helvetica, sans-serif; text-transform: none;">
~/.openmpi/mca-params.conf.</span></div>
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<span style="text-transform: none;">Apparently you can enable this using:</span></div>
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<pre><div class="code-block__code !my-0 !rounded-lg !text-sm !leading-relaxed p-3.5" style="text-align: left; text-indent: 0px; text-transform: none; margin-left: 40px; font-family: "Andale Mono", Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"><code style="font-family: "Andale Mono", Arial, Helvetica, sans-serif;">echo 0 | sudo tee /proc/sys/kernel/yama/ptrace_scope</code></div></pre>
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<span style="text-transform: none;">Cheers</span></div>
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<span style="text-transform: none;">Chris</span></div>
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