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From:   Vincent Guittot <vincent.guittot@linaro.org>
Date:   Thu, 24 Feb 2022 16:29:06 +0100
Message-ID: <CAKfTPtB_GGb2eZqWfmKrY3-Z9spN9wzU4pXMGz38bAZu8ExCMQ@mail.gmail.com>
Subject: Re: [RFC PATCH 0/5] introduce sched-idle balancing
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Abel Wu <wuyun.abel@bytedance.com>,
        Ben Segall <bsegall@google.com>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Ingo Molnar <mingo@redhat.com>,
        Juri Lelli <juri.lelli@redhat.com>,
        Mel Gorman <mgorman@suse.de>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-kernel@vger.kernel.org
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On Thu, 24 Feb 2022 at 16:20, Peter Zijlstra <peterz@infradead.org> wrote:
>
> On Thu, Feb 17, 2022 at 11:43:56PM +0800, Abel Wu wrote:
> > Current load balancing is mainly based on cpu capacity
> > and task util, which makes sense in the POV of overall
> > throughput. While there still might be some improvement
> > can be done by reducing number of overloaded cfs rqs if
> > sched-idle or idle rq exists.
>
> I'm much confused, there is an explicit new-idle balancer and a periodic
> idle balancer already there.

I agree, You failed to explain why newly_idle and periodic idle load
balance are not enough and we need this new one