[Moabusers] Nice - priority in operating system

[Lukasz Skital]

Hi *,

I am new to the list so I introduce my self a little: I am
cluster/grid administartor for EGEE project (http://www.eu-egee.org/).
I also works in few other grid related projects.

One of the project I am involved,  could benefit from following feature:

Preempting mechanism, which, instead of
suspending/killing/requeuing/checkpointig is altering process priority
in operating system (in linux you can use renice to do this).

Is it possible to be done with toruqe/maui? Is it possible with other
resource management system?

If you are not sure, what exactly I request, there is a little background:

We have general purpose grid infrastructure (gLite based) with torque
and maui on clusters. We have some specific soft real-time application
which need to access resources as quick as it is possible, but we want
to avoid static reservations. So the idea is to preempt working low
priority job by our high priority jobs. However, we do not want to
kill or suspend low priority jobs (checkpointing is not supported),
but instead want to renice it, to serve most of CPU cycles high
priority job and the low priority job will maintain its operations
(esp. keeps network connections). So instead of  suspending, the job
is put in to low priority (renice 20) for the time, when high prio job
is running on the same CPU.

Memory constraints is not the case, because our high priority jobs
have low memory requirements.

Best regards,
-- 
Łukasz Skitał   <l.skital at cyfronet.pl>  GG: 1279114