Lachlan, forgive me if I am teaching granny to suck eggs..,, I have recently been workign with cgroups. If you run an interactive job what do you see when cat /proc/self/cgroups Also have you explored in /sys/fs/cgroups and checked what resources are in the cgroups which a job has?
On 14 August 2017 at 07:49, Lachlan Musicman <[email protected]> wrote: > Hola, > > Slurm is complicated software, and sometimes the docs can be dense - I'm > looking for some clarification please. > > We have a system set up with Threads as CPUs. 1 socket, 4 cores, 2 threads > = 8 cpus > > I would like to implement CGroups because some of our users are quite > happy to utilise all threads despite other users. > > We have TaskPlugin=task/cgroup and when testing I noticed that the # of > threads/cpus being allocated was rounded up to the nearest even. I presume > this was due to cgroups marking a core as a cpu, rather than a thread as a > cpu. > > So I set TaskPluginParam=Threads, but slurm is still allowing the use of > more threads than have been requested. > > In particular, I'm running this test: > > #!/bin/bash > #SBATCH --nodes=1 > #SBATCH --ntasks=3 > > stress-ng --cpu 5 --cpu-method all --io 5 --vm 1 --vm-bytes 1G --timeout > 600s --quiet > > > I was hoping that the cgroup would kill the job because of too many cpus, > but that's not how stress-ng works I've discovered. > > Regardless, when running this, I noted that squeue shows I've been > allocated 3 CPUs, but on the server itself, I'm seeing four cpus being used? > > What have I done wrong? Is it possible to have granular control at the > thread level with cgroups? > > cheers > L. > > > ------ > "The antidote to apocalypticism is *apocalyptic civics*. Apocalyptic > civics is the insistence that we cannot ignore the truth, nor should we > panic about it. It is a shared consciousness that our institutions have > failed and our ecosystem is collapsing, yet we are still here — and we are > creative agents who can shape our destinies. Apocalyptic civics is the > conviction that the only way out is through, and the only way through is > together. " > > *Greg Bloom* @greggish https://twitter.com/greggish/ > status/873177525903609857 >
