[slurm-users] scavenger partition/qos

[Hanu Pathuri]

Hello,

I am trying to setup my SLURM cluster. One of thing I want to achieve was to 
schedule jobs which will be run on when there are no high priority tasks.
My understanding is that this can be achieved by either configuring a partition 
with pre-empt mode 'Suspend/Reque' with priority for this being very low or 
have a QOS configured with very low priority.

Here are my questions:

  1.  Is there built-in 'scavenger' feature/partition or 'qos' that I can make 
use of?
  2.  When I created a 'scavenger' partition with lower priority  (preempt 
mode=suspend), and debug partition with higher priority (preempt mode=suspend), 
scheduler is not pre-empting the jobs run on scavenger partition when I submit 
the jobs with debug partition immediately. However if I change the pre-empt 
mode for scavenger partition to 'requeue', pre-emptions happens immediately.
Thanks

[slurm-users] number of tasks that can run on a node without oversubscribing

[Hanu Pathuri]

Hi,
Here is my node information. I am confused with the terminology w.r.t CPU vs 
CORE.
NodeName=hpathuri-linux CPUs=8 RealMemory=15833 Sockets=1 CoresPerSocket=4 
ThreadsPerCore=2 State=UNKNOWN.

I am unable to schedule more than 4 tasks without over subscribing even through 
my configuration looks like this:

SchedulerType=sched/backfill
#SchedulerPort=7321
SelectType=select/cons_res
SelectTypeParameters=CR_Core
PreemptMode=suspend,GANG

Could help clarify what is going on?

I was expecting to schedule 8 tasks.

Thanks