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Date:   Fri, 16 Jun 2023 13:56:24 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Daniel Bristot de Oliveira <bristot@kernel.org>
Cc:     Joel Fernandes <joel@joelfernandes.org>,
        Ingo Molnar <mingo@redhat.com>,
        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>, Mel Gorman <mgorman@suse.de>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Valentin Schneider <vschneid@redhat.com>,
        linux-kernel@vger.kernel.org,
        Luca Abeni <luca.abeni@santannapisa.it>,
        Tommaso Cucinotta <tommaso.cucinotta@santannapisa.it>,
        Thomas Gleixner <tglx@linutronix.de>,
        Vineeth Pillai <vineeth@bitbyteword.org>,
        Shuah Khan <skhan@linuxfoundation.org>
Subject: Re: [RFC PATCH V3 6/6] sched/fair: Implement starvation monitor
Message-ID: <20230616115624.GL83892@hirez.programming.kicks-ass.net>
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On Mon, Jun 12, 2023 at 04:45:54PM +0200, Daniel Bristot de Oliveira wrote:
> On 6/12/23 03:57, Joel Fernandes wrote:

> > Lastly, if the goal is to remove RT throttling code eventually, are
> > you also planning to remove RT group scheduling as well? Are there
> > users of RT group scheduling that might be impacted? On the other
> > hand, RT throttling / group scheduling code can be left as it is
> > (perhaps documenting it as deprecated) and the server stuff can be
> > implemented via a CONFIG option.
> 
> I think that the idea is to have the DL servers eventually replace the group
> schedule. But I also believe that it is better to start by solving the
> throttling and then moving to other constructions on top of the mechanism.

The big problem with the rt group scheduling mess is affinities. Other
than that, yes abosolutely, that crap needs to go.