From:   Valentin Schneider <valentin.schneider@arm.com>
To:     Josef Bacik <josef@toxicpanda.com>
Cc:     peterz@infradead.org, vincent.guittot@linaro.org,
        torvalds@linux-foundation.org, linux-kernel@vger.kernel.org,
        linux-btrfs@vger.kernel.org
Subject: Re: [REGRESSION] 5-10% increase in IO latencies with nohz balance patch
In-Reply-To: <YaUYsUHSKI5P2ulk@localhost.localdomain>
References: <YaUH5GFFoLiS4/3/@localhost.localdomain> <87ee6yc00j.mognet@arm.com> <YaUYsUHSKI5P2ulk@localhost.localdomain>
Date:   Mon, 29 Nov 2021 18:31:17 +0000
Message-ID: <87bl22byq2.mognet@arm.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

On 29/11/21 13:15, Josef Bacik wrote:
> On Mon, Nov 29, 2021 at 06:03:24PM +0000, Valentin Schneider wrote:
>> Would you happen to have execution traces by any chance? If not I should be
>> able to get one out of that fsperf thingie.
>>
>
> I don't, if you want to tell me how I can do it right now.  I've disabled
> everything on this box for now so it's literally just sitting there waiting to
> have things done to it.  Thanks,
>

I see you have Ftrace enabled in your config, so that ought to do it:

  trace-cmd record -e 'sched:*' -e 'cpu_idle' $your_test_cmd

> Josef