Re: [PATCH 07/41] cpuset: Set up interface for nohz flag

[Mike Galbraith]

On Wed, 2012-05-09 at 09:22 -0500, Christoph Lameter wrote: 
> On Wed, 9 May 2012, Mike Galbraith wrote:

> > > isolcpus are not part of load balancer domains.
> >
> > Yup, so if you have an application with an RT component, somewhat
> > sensitive, needs isolation from rest of a big box, but app also has
> > SCHED_OTHER components.  isolcpus is a pain, everything has to be static
> > and nailed to the floor.  Load just works when plugged into a cpuset.
> 
> Well you have low latency requirements. If you code for lowest latency
> then you have to consider cache sizes, cache sharing etc etc. This means
> you will have to nail down everything anyways. Cpusets would just be
> another thing that one has to worry about.
> 
> The loads definitely wont work right if just "plugged into a cpuset".

You're talking about serious RT/HPC.  I'm talking about apps/loads with
modest requirements, like "Please keep that evil nVidia (this that the
other) thing the _hell_ away from me, I cannot deal with it's futzing
around in the kernel for a _full second_ at a time".

-Mike

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/