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Subject: Re: [hwloc-devel] hwloc_cpuset_t to cgroups cpuset conversion
From: Brice Goglin (Brice.Goglin_at_[hidden])
Date: 2012-06-19 02:55:20


Hello,

Isn't this what hwloc_bitmap_list_sscanf/snprintf/asprintf do ? (added
in 1.2.0)

Brice

Le 19/06/2012 08:32, Rayson Ho a écrit :
> hwloc already has code (linux-libnuma.h) for hwloc_cpuset_t to libnuma
> data type conversion. Does it make sense to add functions to convert
> hwloc_cpuset_t types to the cpuset string format used by Linux's
> cgroups?
>
> The cpuset format used by cgroups is not difficult to handle (in fact,
> the user interface is same as/very similar to the older cpuset
> implementation). Eg. create a cpuset that includes CPU 2 & 3 for
> OGS/Grid Engine:
>
> # echo 2-3 > /sys/fs/cgroup/cpuset/gridengine/cpuset.cpus
>
> Ref: http://www.kernel.org/doc/Documentation/cgroups/cpusets.txt
>
>
> We are pinging the list because we use hwloc for topology binding, and
> we also added cgroups support (for a lot of things) in OGS/Grid
> Engine:
>
> http://blogs.scalablelogic.com/2012/05/grid-engine-cgroups-integration.html
>
> We are planning to integrate hwloc & cgroups (and skip libnuma)... And
> we want to choose which method we use at runtime. While hwloc can be
> used by non-root applications, the applications can modify the
> affinity mask themselves and thus they can escape from the "cpuset"
> (as least with the current hwloc implementation that uses
> sched_setaffinity). The cgroups cpuset support is only available to
> root, but once binded, batch jobs running as non-root could not escape
> from the cpuset.
>
> Rayson
>
> ==================================================
> Open Grid Scheduler - The Official Open Source Grid Engine
> http://gridscheduler.sourceforge.net/
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