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Date:   Fri, 24 Mar 2023 19:19:36 +0100
From:   Michal =?utf-8?Q?Koutn=C3=BD?= <mkoutny@suse.com>
To:     Will Deacon <will@kernel.org>
Cc:     Waiman Long <longman@redhat.com>, Tejun Heo <tj@kernel.org>,
        Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Shuah Khan <shuah@kernel.org>, cgroups@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 3/5] cgroup/cpuset: Find another usable CPU if none found
 in current cpuset
Message-ID: <20230324181936.5sf6xjc5a4vacuku@blackpad>
References: <20230306200849.376804-1-longman@redhat.com>
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On Fri, Mar 24, 2023 at 02:32:50PM +0000, Will Deacon <will@kernel.org> wrote:
> So approaches such as killing tasks or rejecting system calls tend not
> to work as well, since you inevitably get divergent behaviour leading
> to functional breakage rather than e.g. performance anomalies.

What about temporary performance drop from 100% to 0% aka freezing the
tasks for the duration of the mismatching affinity config?


> Having said that, the behaviour we currently have in mainline seems to
> be alright, so please don't go out of your way to accomodate these SoCs.

I see. (Just wondering what you think about the fourth option above.)

Thanks,
Michal

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