Re: [PATCH v4 0/4] cpusets,isolcpus: exclude isolcpus from load balancing in cpusets

[Tejun Heo <tj@kernel.org>]

On Tue, Mar 03, 2015 at 06:00:19PM -0500, riel@redhat.com wrote:
> Ensure that cpus specified with the isolcpus= boot commandline
> option stay outside of the load balancing in the kernel scheduler.
> 
> Operations like load balancing can introduce unwanted latencies,
> which is exactly what the isolcpus= commandline is there to prevent.
> 
> Previously, simply creating a new cpuset, without even touching the
> cpuset.cpus field inside the new cpuset, would undo the effects of
> isolcpus=, by creating a scheduler domain spanning the whole system,
> and setting up load balancing inside that domain. The cpuset root
> cpuset.cpus file is read-only, so there was not even a way to undo
> that effect.
> 
> This does not impact the majority of cpusets users, since isolcpus=
> is a fairly specialized feature used for realtime purposes.
> 
> This version fixes the UP compilation issue, in the same way done
> for the other cpumasks.

Can you please repost with Li Zefan <lizefan@huawei.com> and
cgroups@vger.kernel.org cc'd?

Thanks.

-- 
tejun