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Date:   Fri, 29 May 2020 17:57:39 +0100
From:   Mel Gorman <mgorman@suse.de>
To:     Qais Yousef <qais.yousef@arm.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        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>,
        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>,
        Patrick Bellasi <patrick.bellasi@matbug.net>,
        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
Message-ID: <20200529165739.GD3070@suse.de>
References: <20200511154053.7822-1-qais.yousef@arm.com>
 <20200528132327.GB706460@hirez.programming.kicks-ass.net>
 <20200528155800.yjrmx3hj72xreryh@e107158-lin.cambridge.arm.com>
 <20200528161112.GI2483@worktop.programming.kicks-ass.net>
 <20200529100806.GA3070@suse.de>
 <20200529160423.qsrbzxtcx2jslljk@e107158-lin>
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> > A lot of the uclamp functions appear to be inlined so it is not be
> > particularly obvious from a raw profile but it shows up in the annotated
> > profile in activate_task and dequeue_task for example. In the case of
> > dequeue_task, uclamp_rq_dec_id() is extremely expensive according to the
> > annotated profile.
> > 
> > I'm afraid I did not dig into this deeply once I knew I could just disable
> > it even within the distribution.
> 
> Could by any chance the vmlinux (with debug symbols hopefully) and perf.dat are
> still lying around to share?
> 

I didn't preserve the vmlinux files. I can recreate them if you have
problems reproducing this locally. The "perf archive" files and profile
data can be downloaded at
http://www.skynet.ie/~mel/postings/netperf-20200529/profile.tar.gz which
should be enough for an annotated profile to compare with a local run.

-- 
Mel Gorman
SUSE Labs