Thank you Chris, Marcus, Patrick and Ray. I guess i am still a bit confused. We will se what happen when we run a job asking for the CPU’s of the cluster.
_____________________________________________________________________________________________________ Eric F. Alemany System Administrator for Research Division of Radiation & Cancer Biology Department of Radiation Oncology Stanford University School of Medicine Stanford, California 94305 Tel:1-650-498-7969<tel:1-650-498-7969> No Texting Fax:1-650-723-7382<tel:1-650-723-7382> On May 7, 2018, at 4:08 AM, Chris Samuel <ch...@csamuel.org<mailto:ch...@csamuel.org>> wrote: On Monday, 7 May 2018 5:41:27 PM AEST Marcus Wagner wrote: To me it looks like CPUs is the synonym for hardware threads. Interesting, at ${JOB-1} we experimented with HT on a system back in 2013 and I didn't do the slurm.conf side at that time, but then you could only request physical cores and you would be allocated both thread units (unless you lied to Slurm and listed them as physical cores instead). Everything I've ever done since has had ThreadsPerCore=1, until today where we have some KNL nodes which are ThreadsPerCore=4. I can confirm there that you get 4 hardware thread units (a single core) when you request -n 1 -c 1 - here from an interactive job on a KNL node: [csamuel@gina1 ~]$ cat /sys/fs/cgroup/cpuset/$(cat /proc/$$/cpuset)/ cpuset.cpus 0,68,136,204 So in the sense of what you put in slurm.conf you are indeed right, CPUs=boards*sockets*cores*threads, but from the point of view of what you *request* CPUs are just boards*sockets*cores. Confusing! All the best, Chris -- Chris Samuel : http://www.csamuel.org/ : Melbourne, VIC
