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<p>We've hit this before due to RPC saturation. I highly recommend
using max_rpc_cnt and/or defer for scheduling. That should help
alleviate this problem.</p>
<p>-Paul Edmon-<br>
</p>
<div class="moz-cite-prefix">On 8/26/19 2:12 AM, Guillaume Perrault
Archambault wrote:<br>
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cite="mid:CAG1OYp0CTPOpLdfdOUzUh-y=EuWx+xb+U2VGNwBrXJ_9-HTyMQ@mail.gmail.com">
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<div dir="ltr">Hello,
<div><br>
</div>
<div>I wrote a regression-testing toolkit to manage large
numbers of SLURM jobs and their output (the toolkit can be
found <a
href="https://github.com/gobbedy/slurm_simulation_toolkit/"
moz-do-not-send="true">here</a> if anyone is interested).</div>
<div><br>
</div>
<div>To make job launching faster, sbatch commands are forked,
so that numerous jobs may be submitted in parallel.</div>
<div><br>
</div>
<div>We (the cluster admin and myself) are concerned that this
may cause unresponsiveness for other users.</div>
<div><br>
</div>
<div>I cannot say for sure since I don't have visibility over
all users of the cluster, but unresponsiveness doesn't seem to
have occurred so far. That being said, the fact that it hasn't
occurred yet doesn't mean it won't in the future. So I'm
treating this as a ticking time bomb to be fixed asap.</div>
<div><br>
</div>
<div>My questions are the following:</div>
<div>1) Does anyone have experience with large numbers of jobs
submitted in parallel? What are the limits that can be hit?
For example is there some hard limit on how many jobs a SLURM
scheduler can handle before blacking out / slowing down?</div>
<div>2) Is there a way for me to find/measure/ping this resource
limit?</div>
<div>3) How can I make sure I don't hit this resource limit?</div>
<div><br>
</div>
<div>From what I've observed, parallel submission can improve
submission time by a factor at least 10x. This can make a big
difference in users' workflows. </div>
<div><br>
</div>
<div>For that reason I would like to keep the option of
launching jobs sequentially as a last resort.</div>
<div><br>
</div>
<div>Thanks in advance.</div>
<div><br>
</div>
<div>Regards,</div>
<div>Guillaume.</div>
</div>
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