From: Jens Axboe <axboe@kernel.dk>
To: Paolo Valente <paolo.valente@linaro.org>, Tejun Heo <tj@kernel.org>
Cc: Fabio Checconi <fchecconi@gmail.com>,
Arianna Avanzini <avanzini.arianna@gmail.com>,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
ulf.hansson@linaro.org, linus.walleij@linaro.org,
broonie@kernel.org
Subject: Re: [PATCH RFC 01/14] block, bfq: introduce the BFQ-v0 I/O scheduler as an extra scheduler
Date: Sun, 5 Mar 2017 08:16:20 -0700 [thread overview]
Message-ID: <91b856e8-2c14-00b6-fdd8-b9879b1b9952@kernel.dk> (raw)
In-Reply-To: <20170304160131.57366-2-paolo.valente@linaro.org>
On 03/04/2017 09:01 AM, Paolo Valente wrote:
> We tag as v0 the version of BFQ containing only BFQ's engine plus
> hierarchical support. BFQ's engine is introduced by this commit, while
> hierarchical support is added by next commit. We use the v0 tag to
> distinguish this minimal version of BFQ from the versions containing
> also the features and the improvements added by next commits. BFQ-v0
> coincides with the version of BFQ submitted a few years ago [1], apart
> from the introduction of preemption, described below.
>
> BFQ is a proportional-share I/O scheduler, whose general structure,
> plus a lot of code, are borrowed from CFQ.
I'll take a closer look at this in the coming week. But one quick
comment - don't default to BFQ. Both because it might not be fully
stable yet, and also because the performance limitation of it is
quite severe. Whereas deadline doesn't really hurt single queue
flash at all, BFQ will.
Generally, I think that sort of logic should go into a udev rule. If
a device is rotational it should default to BFQ once the dust has
settled.
--
Jens Axboe
next prev parent reply other threads:[~2017-03-05 15:16 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-04 16:01 [PATCH RFC 00/14] Add the BFQ I/O Scheduler to blk-mq Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 01/14] block, bfq: introduce the BFQ-v0 I/O scheduler as an extra scheduler Paolo Valente
2017-03-05 15:16 ` Jens Axboe [this message]
2017-03-05 16:02 ` Paolo Valente
2017-03-06 20:46 ` Jens Axboe
2017-03-14 11:28 ` Paolo Valente
2017-03-06 19:40 ` Bart Van Assche
2017-03-14 14:18 ` Paolo Valente
2017-03-18 12:08 ` Paolo Valente
2017-03-18 15:24 ` Bart Van Assche
2017-03-19 11:45 ` Paolo Valente
2017-03-07 23:22 ` Jens Axboe
2017-03-18 12:41 ` Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 02/14] block, bfq: add full hierarchical scheduling and cgroups support Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 03/14] block, bfq: improve throughput boosting Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 04/14] block, bfq: modify the peak-rate estimator Paolo Valente
2017-03-07 0:47 ` Bart Van Assche
2017-03-04 16:01 ` [PATCH RFC 05/14] block, bfq: add more fairness with writes and slow processes Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 06/14] block, bfq: improve responsiveness Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 07/14] block, bfq: reduce I/O latency for soft real-time applications Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 08/14] block, bfq: preserve a low latency also with NCQ-capable drives Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 09/14] block, bfq: reduce latency during request-pool saturation Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 10/14] block, bfq: add Early Queue Merge (EQM) Paolo Valente
2017-03-07 17:44 ` Jens Axboe
2017-03-15 12:01 ` Paolo Valente
2017-03-15 15:47 ` Jens Axboe
2017-03-15 16:30 ` Jens Axboe
2017-03-15 16:59 ` Paolo Valente
2017-03-15 21:00 ` Jens Axboe
2017-03-18 10:33 ` Paolo Valente
2017-03-15 16:56 ` Jens Axboe
2017-03-15 17:02 ` Paolo Valente
2017-03-15 21:01 ` Jens Axboe
2017-03-04 16:01 ` [PATCH RFC 11/14] block, bfq: reduce idling only in symmetric scenarios Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 12/14] block, bfq: boost the throughput on NCQ-capable flash-based devices Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 13/14] block, bfq: boost the throughput with random I/O on NCQ-capable HDDs Paolo Valente
2017-03-07 0:54 ` Bart Van Assche
2017-03-14 14:12 ` Paolo Valente
2017-03-04 16:01 ` [PATCH RFC 14/14] block, bfq: handle bursts of queue activations Paolo Valente
2017-03-06 7:43 ` [PATCH RFC 00/14] Add the BFQ I/O Scheduler to blk-mq Markus Trippelsdorf
2017-03-31 13:27 ` Paolo Valente
2017-03-07 0:22 ` Bart Van Assche
2017-03-14 14:12 ` Paolo Valente
2017-03-07 1:00 ` Bart Van Assche
2017-03-14 15:35 ` Paolo Valente
2017-03-14 15:42 ` Jens Axboe
2017-03-14 16:32 ` Bart Van Assche
2017-03-18 10:52 ` Paolo Valente
2017-03-18 17:09 ` Linus Walleij
2017-03-18 17:46 ` Bart Van Assche
2017-03-18 20:46 ` Linus Walleij
2017-03-19 12:14 ` Paolo Valente
2017-03-20 18:40 ` Jens Axboe
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=91b856e8-2c14-00b6-fdd8-b9879b1b9952@kernel.dk \
--to=axboe@kernel.dk \
--cc=avanzini.arianna@gmail.com \
--cc=broonie@kernel.org \
--cc=fchecconi@gmail.com \
--cc=linus.walleij@linaro.org \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=paolo.valente@linaro.org \
--cc=tj@kernel.org \
--cc=ulf.hansson@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;
as well as URLs for NNTP newsgroup(s).