"So if they submit a 2 nd job, that job can start but will have to go onto another node, and will again be restricted to 200G? So they can start as many jobs as there are nodes, and each job will be restricted to using 1 node and 200G of memory?"
Yes that's it. We already have MaxNodes=1 so a job can't be spread on multiple nodes.
To be more precise, the limit should be by user and not by job. To illustrate, let's imagine we have 3 empty nodes and a 200G/user/node limit. If a user submit 10 jobs each requesting 100G of memory, there should be 2 jobs running on each worker and 4 jobs pending.
Guillaume
De: "Groner, Rob" rug262@psu.edu À: "Guillaume COCHARD" guillaume.cochard@cc.in2p3.fr Cc: slurm-users@lists.schedmd.com Envoyé: Mardi 24 Septembre 2024 16:37:34 Objet: Re: Max TRES per user and node
Ah, sorry, I didn't catch that from your first post (though you did say it).
So, you are trying to limit the user to no more than 200G of memory on a single node? So if they submit a 2 nd job, that job can start but will have to go onto another node, and will again be restricted to 200G? So they can start as many jobs as there are nodes, and each job will be restricted to using 1 node and 200G of memory? Or can they submit a job asking for 4 nodes, where they are limited to 200G on each node? Or are they limited to a single node, no matter how many jobs?
Rob
From: Guillaume COCHARD guillaume.cochard@cc.in2p3.fr Sent: Tuesday, September 24, 2024 10:09 AM To: Groner, Rob rug262@psu.edu Cc: slurm-users@lists.schedmd.com slurm-users@lists.schedmd.com Subject: Re: Max TRES per user and node Thank you for your answer.
To test it I tried: sacctmgr update qos normal set maxtresperuser=cpu=2 # Then in slurm.conf PartitionName=test […] qos=normal
But then if I submit several 1-cpu jobs only two start and the others stay pending, even though I have several nodes available. So it seems that MaxTRESPerUser is a QoS-wide limit, and doesn't limit TRES per user and per node but rather per user and QoS (or rather partition since I applied the QoS on the partition). Did I miss something?
Thanks again, Guillaume
De: "Groner, Rob" rug262@psu.edu À: slurm-users@lists.schedmd.com, "Guillaume COCHARD" guillaume.cochard@cc.in2p3.fr Envoyé: Mardi 24 Septembre 2024 15:45:08 Objet: Re: Max TRES per user and node
You have the right idea.
On that same page, you'll find MaxTRESPerUser, as a QOS parameter.
You can create a QOS with the restrictions you'd like, and then in the partition definition, you give it that QOS. The QOS will then apply its restrictions to any jobs that use that partition.
Rob
From: Guillaume COCHARD via slurm-users slurm-users@lists.schedmd.com Sent: Tuesday, September 24, 2024 9:30 AM To: slurm-users@lists.schedmd.com slurm-users@lists.schedmd.com Subject: [slurm-users] Max TRES per user and node Hello,
We are looking for a method to limit the TRES used by each user on a per-node basis. For example, we would like to limit the total memory allocation of jobs from a user to 200G per node.
There is MaxTRESperNode ( [ https://slurm.schedmd.com/sacctmgr.html#OPT_MaxTRESPerNode | https://nam10.safelinks.protection.outlook.com/?url=https%3A%2F%2Fslurm.sche... ] ), but unfortunately, this is a per-job limit, not per user.
Ideally, we would like to apply this limit on partitions and/or QoS. Does anyone know if this is possible and how to achieve it?
Thank you,