[torquedev] cpuset support

[Prakash Velayutham]

Hi Garrick,

Can I ask a stupid question like, what does the current cpuset code in  
resmom do?

Thanks,
Prakash

On Nov 12, 2007, at 7:17 PM, Garrick Staples wrote:

> I just bumped into Chris Samuel at his (rather barren) booth here at  
> SC07 and I think we just designed cpuset support.
>
> Here's what we came up with...
>
> On startup, pbs_mom will create /dev/cpuset/torque (with all cpus)  
> if it
> doesn't already exist and move itself to it.  This allows the admin  
> to stuff
> pbs_mom inside a smaller cpuset if desired by creating it in the  
> initscript.
> We will call this the "torqueset".
>
> When a job starts, pbs_mom will create a per-job cpuset under the  
> torqueset
> with the correct cpus called the "jobset".  It will do this after  
> prologue,
> which allows the admin to pre-create it if desired.  This happens on  
> all nodes.
>
> Also, per-vnode cpusets will also be created under the jobset at job  
> start.
>
> pbs_mom will run the batch script inside of the jobset and all TM  
> spawn
> requests will run in the vnodeset.
>
> You end up with cpusets that look like:
>  /dev/cpuset/torque/job-123.pbsserver.foo.edu/vnode-4
>
> Job exit will consist of ensuring the cpusets are empty (killing  
> processes)
> before removing them.
>
> Exclusive cpusets can't be used because of suspended jobs.
>
> All mems will be added to all cpusets unless someone comes up with  
> another idea.
>
> This seems pretty simple to implement, doesn't require any build  
> deps, and
> makes sense to me.  Any thoughts?