<div dir="ltr"><div>We also run diskless. In the slurm.conf we round down on memory so slurm does not have the total budget to work with and use a default memory per job value reflecting declared memory/# of threads per node. If users don't declarememory limit we are fine. If they declare more we are fine too. Mostly. We had to turn off memory enforcement as the job memory usage is very uneven during runtime but with the above we have seldom had problems.</div><div><br></div><div>Doug<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, Mar 14, 2019 at 3:57 AM david baker <<a href="mailto:djbaker12@gmail.com">djbaker12@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div dir="ltr">Hello Paul,<div><br></div><div>Thank you for your advice. That all makes sense. We're running diskless compute nodes and so the usable memory is less than the total memory. So I have added a memory check to my job_submit.lua -- see below. I think that all makes sense.</div><div><br></div><div>Best regards,</div><div>David</div><div><br></div><div><div>-- Check memory/node is valid</div><div> if job_desc.min_mem_per_cpu == 9223372036854775808 then</div><div> job_desc.min_mem_per_cpu = 4300</div><div> end</div><div><br></div><div> memory = job_desc.min_mem_per_cpu * job_desc.min_cpus</div><div><br></div><div> if memory > 172000 then</div><div> slurm.log_user("You cannot request more than 172000 Mbytes per node")</div><div> slurm.log_user("memory is: %u",memory)</div><div> return slurm.ERROR</div><div> end</div></div><div><br></div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Mar 12, 2019 at 4:48 PM Paul Edmon <<a href="mailto:pedmon@cfa.harvard.edu" target="_blank">pedmon@cfa.harvard.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<p>Slurm should automatically block or reject jobs that can't run on
that partition in terms of memory usage for a single node. So you
shouldn't need to do anything. If you need something less than
the max memory per node then you will need to enforce some
limits. We do this via a jobsubmit lua script. That would be my
recommended method.<br>
</p>
<p><br>
</p>
<p>-Paul Edmon-</p>
<p><br>
</p>
<div class="gmail-m_-7672031880103951612gmail-m_-7371107165191797214moz-cite-prefix">On 3/12/19 12:31 PM, David Baker wrote:<br>
</div>
<blockquote type="cite">
<div id="gmail-m_-7672031880103951612gmail-m_-7371107165191797214divtagdefaultwrapper" style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif" dir="ltr">
<p style="margin-top:0px;margin-bottom:0px"><span>Hello,</span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><br>
</span></p>
<p style="margin-top:0px;margin-bottom:0px"><span>I have set up a
serial queue to run small jobs in the cluster. Actually, I
route jobs to this queue using the job_submit.lua script.
Any 1 node job using up to 20 cpus is routed to this queue,
unless a user submits their job with an exclusive flag. </span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><br>
</span></p>
<p style="margin-top:0px;margin-bottom:0px"><span>The partition is
shared and so I defined memory to be a resource. I've set
default memory/cpu to be 4300 Mbytes. There are 40 cpus
installed in the nodes and the usable memory is circa 17200
Mbytes -- hence my default mem/cpu.<span></span></span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><br>
</span></p>
<p style="margin-top:0px;margin-bottom:0px"><span>The compute nodes
are defined with <span>RealMemory=190000, by the way.</span></span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><span><br>
</span></span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><span>I am curious
to understand how I can impose a memory limit on the jobs
that are submitted to this partition. It doesn't make any
sense to request more than the total usable memory on the
nodes. So could anyone please advise me how to ensure that
users cannot request more than the usable memory on the
nodes.</span></span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><span><br>
</span></span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><span>Best
regards,</span></span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><span>David</span></span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><br>
</span></p>
<p style="margin-top:0px;margin-bottom:0px"><span>PartitionName=serial
nodes=red[460-464] Shared=Yes MaxCPUsPerNode=40
DefaultTime=02:00:00 MaxTime=60:00:00 QOS=serial
SelectTypeParameters=CR_Core_Memory
<b>DefMemPerCPU=4300</b> State=UP
AllowGroups=jfAccessToIridis5 PriorityJobFactor=10
PreemptMode=off</span><br>
</p>
<p style="margin-top:0px;margin-bottom:0px"><span><br>
</span></p>
<p style="margin-top:0px;margin-bottom:0px"><span><br>
</span></p>
</div>
</blockquote>
</div>
</blockquote></div>
</blockquote></div>