Message-ID: <08e95d68-7ba9-44d0-da85-41dc244b4c99@bytedance.com>
Date:   Wed, 17 Nov 2021 15:07:43 +0800
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Subject: Re: Re: Re: Re: Re: Re: [PATCH v1] sched/numa: add per-process
 numa_balancing
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To:     Mel Gorman <mgorman@suse.de>
Cc:     Jonathan Corbet <corbet@lwn.net>, Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ben Segall <bsegall@google.com>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        linux-api@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
        linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org
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From:   Gang Li <ligang.bdlg@bytedance.com>
In-Reply-To: <20211109162647.GY3891@suse.de>
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On 11/10/21 12:26 AM, Mel Gorman wrote:
> 
> Of those two, I agree with the second one, it would be tricky to implement
> but the first one is less clear. This is based on an assumption. If prctl
> exists to enable/disable NUMA baalancing, it's possible that someone
> else would want to control NUMA balancing on a cgroup basis instead of
> globally which would run into the same type of concerns -- different
> semantics depending on the global tunable.
> 

Hi!

You talk about the "semantics" of NUMA balancing between global, cgroup 
and process. While I read the kernel doc "NUMA Memory Policy", it occur 
to me that we may have a "NUMA Balancing Policy".

Since you are the reviewer of CONFIG_NUMA_BALANCING. I would like to 
discuss the need for introducing "NUMA Balancing Policy" with you. Is 
this worth doing?