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<p class="MsoNormal">I want to launch an MPICH job with sbatch with one task per node (each a manager), while also reserving a certain number of cores on each node for the managers to fill up with spawned workers (via MPI_Comm_spawn). I’d like to avoid using
–exclusive.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I tried the arguments –ntasks=20 –cpus-per-task=24, but it appears that 20 * 24 tasks will be launched. Is there a way to reserve cores without immediately launching tasks on them? Thanks for any help.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">sbatch: defined options<o:p></o:p></p>
<p class="MsoNormal">sbatch: -------------------- --------------------<o:p></o:p></p>
<p class="MsoNormal">sbatch: cpus-per-task : 24<o:p></o:p></p>
<p class="MsoNormal">sbatch: ignore-pbs : set<o:p></o:p></p>
<p class="MsoNormal">sbatch: ntasks : 20<o:p></o:p></p>
<p class="MsoNormal">sbatch: test-only : set<o:p></o:p></p>
<p class="MsoNormal">sbatch: verbose : 1<o:p></o:p></p>
<p class="MsoNormal">sbatch: -------------------- --------------------<o:p></o:p></p>
<p class="MsoNormal">sbatch: end of defined options<o:p></o:p></p>
<p class="MsoNormal">sbatch: Linear node selection plugin loaded with argument 4<o:p></o:p></p>
<p class="MsoNormal">sbatch: select/cons_res loaded with argument 4<o:p></o:p></p>
<p class="MsoNormal">sbatch: Cray/Aries node selection plugin loaded<o:p></o:p></p>
<p class="MsoNormal">sbatch: select/cons_tres loaded with argument 4<o:p></o:p></p>
<p class="MsoNormal">sbatch: Job 34274 to start at 2021-11-25T12:15:05 using <b><span style="color:red">480 processors</span></b><span style="color:red">
</span>on nodes n[001-020] in partition normal<o:p></o:p></p>
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