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Subject: Re: [External] Re: [PATCH] psi: Add PSI_CPU_FULL state
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com,
        vincent.guittot@linaro.org, rostedt@goodmis.org,
        dietmar.eggemann@arm.com, linux-kernel@vger.kernel.org,
        songmuchun@bytedance.com
References: <20210207072402.67532-1-zhouchengming@bytedance.com>
 <YCGAYEiyTKCO71E3@cmpxchg.org>
From:   Chengming Zhou <zhouchengming@bytedance.com>
Message-ID: <2cb984f3-fb8b-df26-31a2-8a091213d87e@bytedance.com>
Date:   Tue, 9 Feb 2021 09:49:34 +0800
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在 2021/2/9 上午2:18, Johannes Weiner 写道:

> On Sun, Feb 07, 2021 at 03:24:02PM +0800, Chengming Zhou wrote:
>> The FULL state doesn't exist for the CPU resource at the system level,
>> but exist at the cgroup level, means all non-idle tasks in a cgroup are
>> delayed on the CPU resource which used by others outside of the cgroup.
>>
>> Co-developed-by: Muchun Song <songmuchun@bytedance.com>
>> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
>> Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
> Acked-by: Johannes Weiner <hannes@cmpxchg.org>
>
> That metric's come up in our production environment recently as well,
> it makes a lot of sense.
>
> In addition to outside competition, this also applies to downtimes
> enforced by cpu.max - another cgroup usecase that is worth mentioning
> in the changelog & code comment.

Thank you, I will add this and send patch-v2.

> Thanks