[slurm-users] hi-priority partition and preemption

[Loris Bennett]

Hi Fabrizio,

Fabrizio Roccato <f.roccato at isac.cnr.it> writes:

> Hi all,
> 	i'm trying to have two overlapping partition, say normal and hi-pri,
> so that when jobs are launched in the second one they can preempt the jobs
> allready running in the first one, automatically putting them in suspend
> state. After completition, the jobs in the normal partition must be
> automatically resumed.
>
> here are my (relevant) slurm.conf settings:
>
>> PreemptMode=suspend,gang
>> PreemptType=preempt/partition_prio
>> 
>> PartitionName=normal Nodes=node0[01-08] MaxTime=1800
>> PriorityTier=100 AllowAccounts=group1,group2 OverSubscribe=FORCE:20
>> PreemptMode=suspend
>> PartitionName=hi-pri Nodes=node0[01-08] MaxTime=360 PriorityTier=500
>> AllowAccounts=group2 OverSubscribe=FORCE:20 PreemptMode=off
>
> But so, jobs in the hi-pri partition where put in PD state and the ones
> allready running in the normal partition continue in their R status.
> What  i'm wrong? What i'm missing?

We don't do anything like this so the following may be incorrect.
However, my understanding is that even if two partitions include the
same node, the node can only be in one partition at one time.  So if a
job requests the partition 'normal' and the job starts, that node is the
in the partition 'normal' only, so no job requesting 'hi-prio' can start
on the node, because it is not a member of that partition.

We use QOS to set different priorities, but we don't use preemption.

> Since i have jobs thath must run at specific time and must have priority over
> all others, is this the correct way to do?

For this I would probably use a recurring reservation.

Cheers,

Loris

> Thanks 
>
> FR 
-- 
Dr. Loris Bennett (Herr/Mr)
ZEDAT, Freie Universität Berlin