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Sender: Tejun Heo <htejun@gmail.com>
Date:   Wed, 21 Sep 2022 07:12:12 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Vincent Guittot <vincent.guittot@linaro.org>
Cc:     Qais Yousef <qais.yousef@arm.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>, mingo@redhat.com,
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        qperret@google.com, tim.c.chen@linux.intel.com, joshdon@google.com
Subject: Re: [PATCH v4 6/8] sched/fair: Add sched group latency support
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On Wed, Sep 21, 2022 at 07:02:57PM +0200, Vincent Guittot wrote:
> > One option could be just using the same mapping as cpu.weight so that 100
> > maps to neutral, 10000 maps close to -20, 1 maps close to 19. It isn't great
> > that the value can't be interpreted in any intuitive way (e.g. a time
> > duration based interface would be a lot easier to grok even if it still is
> > best effort) but if that's what the per-task interface is gonna be, it'd be
> > best to keep cgroup interface in line.
> 
> I would prefer a signed range like the [-1000:1000] as the behavior is
> different for sensitive and non sensitive task unlike the cpu.weight
> which is reflect that a bigger value get more

How about just sticking with .nice?

-- 
tejun