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Date: Mon, 23 Apr 2018 15:57:56 +0200
From: Juri Lelli <juri.lelli@redhat.com>
To: Waiman Long <longman@redhat.com>
Cc: Tejun Heo <tj@kernel.org>, Li Zefan <lizefan@huawei.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
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Subject: Re: [PATCH v7 0/5] cpuset: Enable cpuset controller in default
 hierarchy
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On 23/04/18 15:07, Juri Lelli wrote:
> Hi Waiman,
> 
> On 19/04/18 09:46, Waiman Long wrote:
> > v7:
> >  - Add a root-only cpuset.cpus.isolated control file for CPU isolation.
> >  - Enforce that load_balancing can only be turned off on cpusets with
> >    CPUs from the isolated list.
> >  - Update sched domain generation to allow cpusets with CPUs only
> >    from the isolated CPU list to be in separate root domains.
> 

Guess I'll be adding comments as soon as I stumble on something unclear
(to me :), hope that's OK (shout if I should do it differently).

The below looked unexpected to me:

root@debian-kvm:/sys/fs/cgroup# cat g1/cpuset.cpus
2-3
root@debian-kvm:/sys/fs/cgroup# cat g1/cpuset.mems

root@debian-kvm:~# echo $$ > /sys/fs/cgroup/g1/cgroup.threads
root@debian-kvm:/sys/fs/cgroup# cat g1/cgroup.threads
2312

So I can add tasks to groups with no mems? Or is it this only true in my
case with a single mem node? Or maybe it's inherited from root group
(slightly confusing IMHO if that's the case).