clu2's notes: Notes on cpuset

cpuset

See here about what's cpuset.

If cpuset is in effect, then you should see something like this:

$ cat /proc/self/cpuset 
/torque/258.k07n14.ccr.buffalo.edu

$ ls /dev/cpuset/torque/258.k07n14.ccr.buffalo.edu
./   1/             cpus           memory_migrate      memory_spread_slab  sched_load_balance
../  cgroup.procs   mem_exclusive  memory_pressure     mems                sched_relax_domain_level
0/   cpu_exclusive  mem_hardwall   memory_spread_page  notify_on_release   tasks

$ cat /dev/cpuset/torque/258.k07n14.ccr.buffalo.edu/cpus
2-3

Above shows that all processes created by your shell (/proc/self) can only be run on core #2 and #3.

If cpuset is not working, make sure the NUMA/SMP is enabled:

$ dmesg|grep NUMA

NUMA: Allocated memnodemap from a000 - a140
NUMA: Using 31 for the hash shift.