All of lore.kernel.org
 help / color / mirror / Atom feed
From: Mike Galbraith <efault@gmx.de>
To: Mel Gorman <mgorman@techsingularity.net>,
	Paolo Valente <paolo.valente@linaro.org>
Cc: Jens Axboe <axboe@kernel.dk>,
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
	ulf.hansson@linaro.org, broonie@kernel.org,
	lee.tibbert@gmail.com, oleksandr@natalenko.name
Subject: Re: [PATCH BUGFIX/IMPROVEMENT V2 0/3] three bfq fixes restoring service guarantees with random sync writes in bg
Date: Thu, 31 Aug 2017 19:06:06 +0200	[thread overview]
Message-ID: <1504199166.666.11.camel@gmx.de> (raw)
In-Reply-To: <20170831144257.oa5nm6vzihpam6kw@techsingularity.net>

On Thu, 2017-08-31 at 15:42 +0100, Mel Gorman wrote:
> On Thu, Aug 31, 2017 at 08:46:28AM +0200, Paolo Valente wrote:
> > [SECOND TAKE, with just the name of one of the tester fixed]
> >=20
> > Hi,
> > while testing the read-write unfairness issues reported by Mel, I
> > found BFQ failing to guarantee good responsiveness against heavy
> > random sync writes in the background, i.e., multiple writers doing
> > random writes and systematic fdatasync [1]. The failure was caused by
> > three related bugs, because of which BFQ failed to guarantee to
> > high-weight processes the expected fraction of the throughput.
> >=20
>=20
> Queued on top of Ming's most recent series even though that's still a wor=
k
> in progress. I should know in a few days how things stand.

It seems to have cured an interactivity issue I regularly meet during
kbuild final link/depmod phase of fat kernel kbuild, especially bad
with evolution mail usage during that on spinning rust. =C2=A0Can't really
say for sure given this is not based on measurement.

	-Mike=C2=A0

WARNING: multiple messages have this Message-ID (diff)
From: Mike Galbraith <efault@gmx.de>
To: Mel Gorman <mgorman@techsingularity.net>,
	Paolo Valente <paolo.valente@linaro.org>
Cc: Jens Axboe <axboe@kernel.dk>,
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
	ulf.hansson@linaro.org, broonie@kernel.org,
	lee.tibbert@gmail.com, oleksandr@natalenko.name
Subject: Re: [PATCH BUGFIX/IMPROVEMENT V2 0/3] three bfq fixes restoring service guarantees with random sync writes in bg
Date: Thu, 31 Aug 2017 19:06:06 +0200	[thread overview]
Message-ID: <1504199166.666.11.camel@gmx.de> (raw)
In-Reply-To: <20170831144257.oa5nm6vzihpam6kw@techsingularity.net>

On Thu, 2017-08-31 at 15:42 +0100, Mel Gorman wrote:
> On Thu, Aug 31, 2017 at 08:46:28AM +0200, Paolo Valente wrote:
> > [SECOND TAKE, with just the name of one of the tester fixed]
> > 
> > Hi,
> > while testing the read-write unfairness issues reported by Mel, I
> > found BFQ failing to guarantee good responsiveness against heavy
> > random sync writes in the background, i.e., multiple writers doing
> > random writes and systematic fdatasync [1]. The failure was caused by
> > three related bugs, because of which BFQ failed to guarantee to
> > high-weight processes the expected fraction of the throughput.
> > 
> 
> Queued on top of Ming's most recent series even though that's still a work
> in progress. I should know in a few days how things stand.

It seems to have cured an interactivity issue I regularly meet during
kbuild final link/depmod phase of fat kernel kbuild, especially bad
with evolution mail usage during that on spinning rust.  Can't really
say for sure given this is not based on measurement.

	-Mike 

  reply	other threads:[~2017-08-31 17:06 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-31  6:46 [PATCH BUGFIX/IMPROVEMENT V2 0/3] three bfq fixes restoring service guarantees with random sync writes in bg Paolo Valente
2017-08-31  6:46 ` [PATCH BUGFIX/IMPROVEMENT V2 1/3] block, bfq: make lookup_next_entity push up vtime on expirations Paolo Valente
2017-08-31  6:46 ` [PATCH BUGFIX/IMPROVEMENT V2 2/3] block, bfq: remove direct switch to an entity in higher class Paolo Valente
2017-08-31  6:46 ` [PATCH BUGFIX/IMPROVEMENT V2 3/3] block, bfq: guarantee update_next_in_service always returns an eligible entity Paolo Valente
2017-08-31 14:21 ` [PATCH BUGFIX/IMPROVEMENT V2 0/3] three bfq fixes restoring service guarantees with random sync writes in bg Jens Axboe
2017-08-31 14:42 ` Mel Gorman
2017-08-31 17:06   ` Mike Galbraith [this message]
2017-08-31 17:06     ` Mike Galbraith
2017-08-31 17:12     ` Paolo Valente
2017-08-31 17:12       ` Paolo Valente
2017-08-31 17:31       ` Mike Galbraith
2017-08-31 17:31         ` Mike Galbraith
2017-09-04  8:14   ` Mel Gorman
2017-09-04  8:55     ` Paolo Valente
2017-09-04  8:55       ` Paolo Valente
2017-09-04  9:07     ` Ming Lei

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=1504199166.666.11.camel@gmx.de \
    --to=efault@gmx.de \
    --cc=axboe@kernel.dk \
    --cc=broonie@kernel.org \
    --cc=lee.tibbert@gmail.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mgorman@techsingularity.net \
    --cc=oleksandr@natalenko.name \
    --cc=paolo.valente@linaro.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.