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From:   Patrick Bellasi <patrick.bellasi@matbug.net>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Qais Yousef <qais.yousef@arm.com>,
        Giovanni Gherdovich <ggherdovich@suse.cz>,
        Ingo Molnar <mingo@redhat.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Jonathan Corbet <corbet@lwn.net>,
        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>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Iurii Zaikin <yzaikin@google.com>,
        Quentin Perret <qperret@google.com>,
        Valentin Schneider <valentin.schneider@arm.com>,
        Pavan Kondeti <pkondeti@codeaurora.org>,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 1/2] sched/uclamp: Add a new sysctl to control RT default boost value
In-reply-to: <20200528182913.GQ2483@worktop.programming.kicks-ass.net>
Message-ID: <878shb3mj6.derkling@matbug.net>
Date:   Thu, 28 May 2020 21:08:29 +0200
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[+Giovanni]

On Thu, May 28, 2020 at 20:29:14 +0200, Peter Zijlstra <peterz@infradead.org> wrote...

> On Thu, May 28, 2020 at 05:51:31PM +0100, Qais Yousef wrote:

>> I had a humble try to catch the overhead but wasn't successful. The observation
>> wasn't missed by us too then.
>
> Right, I remember us doing benchmarks when we introduced all this and
> clearly we missed something. I would be good if Mel can share which
> benchmark hurt most so we can go have a look.

Indeed, would be great to have a description of their test setup and
results. Perhaps Giovanni can also support us on that.