LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Tejun Heo <tj@kernel.org>
To: brookxu <brookxu.cn@gmail.com>
Cc: axboe@kernel.dk, cgroups@vger.kernel.org,
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] blk-throtl: optimize IOPS throttle for large IO scenarios
Date: Tue, 27 Jul 2021 21:48:06 -1000	[thread overview]
Message-ID: <YQELtmeLjlDHCk2i@mtj.duckdns.org> (raw)
In-Reply-To: <fab343e8-5929-fb30-90e3-b5b6bd34702a@gmail.com>

Hello,

On Wed, Jul 28, 2021 at 10:33:20AM +0800, brookxu wrote:
> If we do this, I think we will encounter some problems, as follows:
> 1. blk-throttle is now at the top of the IO stack. Changing the position of the throttle hook
>    will make this mechanism invalid for some devices.
> 2. We may also need to add a new hook to handle back-merge, otherwise I think the isolation
>    effect will be worse in the sequential IO scene.
> 3. Since bio has entered the IO stack, if it is suspended and resubmitted by blk-throttle,
>    then there is an IO stack reentry problem, which I think may cause many small problems.

Yeah, you're right. I don't think it's worth rocking the boat with
blk-throtl at this point. An extra callback it is then.

Thanks.

-- 
tejun

      reply	other threads:[~2021-07-28  7:48 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-16  6:22 brookxu
2021-07-16 16:09 ` Tejun Heo
2021-07-16 23:07   ` brookxu
2021-07-19 16:35   ` brookxu
2021-07-26 21:46     ` Tejun Heo
2021-07-27  3:06       ` brookxu
2021-07-27 16:21         ` Tejun Heo
2021-07-28  2:33           ` brookxu
2021-07-28  7:48             ` Tejun Heo [this message]

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=YQELtmeLjlDHCk2i@mtj.duckdns.org \
    --to=tj@kernel.org \
    --cc=axboe@kernel.dk \
    --cc=brookxu.cn@gmail.com \
    --cc=cgroups@vger.kernel.org \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --subject='Re: [PATCH] blk-throtl: optimize IOPS throttle for large IO scenarios' \
    /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

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).