mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Beata Michalska <beata.michalska@arm.com>
Cc: Joel Fernandes <joel@joelfernandes.org>,
	Valentin Schneider <valentin.schneider@arm.com>,
	Quentin Perret <qperret@google.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Qais Yousef <qais.yousef@arm.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Viresh Kumar <viresh.kumar@linaro.org>
Subject: Re: iowait boost is broken
Date: Tue, 8 Jun 2021 19:46:54 +0200	[thread overview]
Message-ID: <YL+tDv/EL5ogf/0w@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20210607191031.GA12489@e120325.cambridge.arm.com>

On Mon, Jun 07, 2021 at 08:10:32PM +0100, Beata Michalska wrote:
> So back to the expectations.
> The main problem, as I see it, is what do we actually want to achieve with
> the I/O boosting? Is it supposed to compensate the time lost while waiting
> for the I/O request to be completed or is is supposed to optimize the rate
> at which I/O requests are being made. 

The latter, you want to increase the race of submission.

> Do we want to boost I/O bound tasks by
> default, no limits applied  or should we care about balancing performance
> vs power ? And unless those expectations are clearly stated, we might not
> get too far with any changes, really.

You want to not increase power beyond what is needed to match the rate
of processing I suppose.

  parent reply	other threads:[~2021-06-08 17:47 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-07 16:19 Joel Fernandes
2021-06-07 19:10 ` Beata Michalska
2021-06-08  9:26   ` Qais Yousef
2021-06-08 17:46   ` Peter Zijlstra [this message]
2021-06-09  9:50     ` Quentin Perret
2021-06-10 15:28       ` Qais Yousef
2021-06-10 13:33     ` Beata Michalska
2021-06-08 19:09   ` Joel Fernandes
2021-06-10 13:30     ` Beata Michalska
2021-06-10 18:52       ` Joel Fernandes

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=YL+tDv/EL5ogf/0w@hirez.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=beata.michalska@arm.com \
    --cc=joel@joelfernandes.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=qais.yousef@arm.com \
    --cc=qperret@google.com \
    --cc=valentin.schneider@arm.com \
    --cc=vincent.guittot@linaro.org \
    --cc=viresh.kumar@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®