Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Open MPI User's mailing list

Subject: Re: [OMPI users] memory limits on remote nodes
From: Reuti (reuti_at_[hidden])
Date: 2010-10-07 04:55:20


Am 07.10.2010 um 01:55 schrieb David Turner:

> Hi,
>
> We would like to set process memory limits (vmemoryuse, in csh
> terms) on remote processes. Our batch system is torque/moab.

Isn't it possible to set this up in torque/moab directly? In SGE I would simply define h_vmem and it's per slot then; and with a tight integration all Open MPI processes will be children of sge_execd and the limit will be enforced.

-- Reuti

> The nodes of our cluster each have 24GB of physical memory, of
> which 4GB is taken up by the kernel and the root file system.
> Note that these are diskless nodes, so no swap either.
>
> We can globally set the per-process limit to 2.5GB. This works
> fine if applications run "packed": 8 MPI tasks running on each
> 8-core node, for an aggregate limit of 20GB. However, if a job
> only wants to run 4 tasks, the soft limit can safely be raised
> to 5GB. 2 tasks, 10GB. 1 task, the full 20GB.
>
> Upping the soft limit in the batch script itself only affects
> the "head node" of the job. Since limits are not part of the
> "environment", I can find no way propagate them to remote nodes.
>
> If I understand how this all works, the remote processes are
> started by orted, and therefore inherit its limits. Is there
> any sort of orted configuration that can help here? Any other
> thoughts about how to approach this?
>
> Thanks!
>
> --
> Best regards,
>
> David Turner
> User Services Group email: dpturner_at_[hidden]
> NERSC Division phone: (510) 486-4027
> Lawrence Berkeley Lab fax: (510) 486-4316
> _______________________________________________
> users mailing list
> users_at_[hidden]
> http://www.open-mpi.org/mailman/listinfo.cgi/users