From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH v4] cpuset: Enable cpuset controller in default hierarchy
Date: Fri, 9 Mar 2018 23:17:36 +0100
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To: Waiman Long <longman@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>, Tejun Heo <tj@kernel.org>, Li Zefan <lizefan@huawei.com>, Johannes Weiner <hannes@cmpxchg.org>, Ingo Molnar <mingo@redhat.com>, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kernel-team@fb.com, pjt@google.com, luto@amacapital.net, torvalds@linux-foundation.org, Roman Gushchin <guro@fb.com>

On Fri, Mar 09, 2018 at 03:43:34PM -0500, Waiman Long wrote:
> The isolcpus= parameter just reduce the cpus available to the rests of
> the system. The cpuset controller does look at that value and make
> adjustment accordingly, but it has no dependence on exclusive cpu/mem
> features of cpuset.

The isolcpus= boot param is donkey shit and needs to die. cpuset _used_
to be able to fully replace it, but with the advent of cgroup 'feature'
this got lost.

And instead of fixing it, you're making it _far_ worse. You completely
removed all the bits that allow repartitioning the scheduler domains.

Mike is completely right, full NAK on any such approach.