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: Mon, 26 Jul 2021 11:46:39 -1000 [thread overview]
Message-ID: <YP8tPwkJNMAcjDqk@mtj.duckdns.org> (raw)
In-Reply-To: <957ab14d-c4bc-32f0-3f7d-af98832ab955@gmail.com>
Hello,
On Tue, Jul 20, 2021 at 12:35:54AM +0800, brookxu wrote:
> In order to avoid code duplication and IOPS stability problems caused by estimating
> the equivalent number of IOs, and to avoid potential deadlock problems caused by
> synchronization through queue_lock. I tried to count the number of splited IOs in
> the current window through two atomic counters. Add the value of the atomic variable
> when calculating io_disp[rw], which can also avoid the problem of inaccurate IOPS in
> large IO scenarios. How do you think of this approach? Thanks for your time.
I guess it's okay but am still not a big fan of adding another hook. This is
primarily because blk-throtl is sitting too early in the stack - e.g. rq_qos
is doing the same thing but sits after the split path - and it's a bit nasty
to add an additional hook for it.
Do you think it can be an option to relocate the blk-throtl hooks to the
same spots as rq-qos or, even better, make it use rq-qos?
Thanks.
--
tejun
next prev parent reply other threads:[~2021-07-26 21:46 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-16 6:22 [PATCH] blk-throtl: optimize IOPS throttle for large IO scenarios 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 [this message]
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
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=YP8tPwkJNMAcjDqk@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 \
/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;
as well as URLs for NNTP newsgroup(s).