linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: Maxim Patlasov <MPatlasov@parallels.com>
Cc: karl.kiniger@med.ge.com, jack@suse.cz,
	linux-kernel@vger.kernel.org, t.artem@lycos.com,
	linux-mm@kvack.org, mgorman@suse.de, tytso@mit.edu,
	fengguang.wu@intel.com, torvalds@linux-foundation.org,
	mpatlasov@parallels.com
Subject: Re: [PATCH] mm: add strictlimit knob
Date: Mon, 4 Nov 2013 14:01:04 -0800	[thread overview]
Message-ID: <20131104140104.7936d263258a7a6753eb325e@linux-foundation.org> (raw)
In-Reply-To: <20131101142941.1161.40314.stgit@dhcp-10-30-17-2.sw.ru>

On Fri, 01 Nov 2013 18:31:40 +0400 Maxim Patlasov <MPatlasov@parallels.com> wrote:

> "strictlimit" feature was introduced to enforce per-bdi dirty limits for
> FUSE which sets bdi max_ratio to 1% by default:
> 
> http://www.http.com//article.gmane.org/gmane.linux.kernel.mm/105809
> 
> However the feature can be useful for other relatively slow or untrusted
> BDIs like USB flash drives and DVD+RW. The patch adds a knob to enable the
> feature:
> 
> echo 1 > /sys/class/bdi/X:Y/strictlimit
> 
> Being enabled, the feature enforces bdi max_ratio limit even if global (10%)
> dirty limit is not reached. Of course, the effect is not visible until
> max_ratio is decreased to some reasonable value.

I suggest replacing "max_ratio" here with the much more informative
"/sys/class/bdi/X:Y/max_ratio".

Also, Documentation/ABI/testing/sysfs-class-bdi will need an update
please.

>  mm/backing-dev.c |   35 +++++++++++++++++++++++++++++++++++
>  1 file changed, 35 insertions(+)
> 

I'm not really sure what to make of the patch.  I assume you tested it
and observed some effect.  Could you please describe the test setup and
the effects in some detail?

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2013-11-04 22:01 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20131031142612.GA28003@kipc2.localdomain>
2013-11-01 14:31 ` Maxim Patlasov
2013-11-04 22:01   ` Andrew Morton [this message]
2013-11-06 14:30     ` Maxim Patlasov
2013-11-06 15:05     ` [PATCH] mm: add strictlimit knob -v2 Maxim Patlasov
2013-11-07 12:26       ` Henrique de Moraes Holschuh
2013-11-22 23:45       ` Andrew Morton

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=20131104140104.7936d263258a7a6753eb325e@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=MPatlasov@parallels.com \
    --cc=fengguang.wu@intel.com \
    --cc=jack@suse.cz \
    --cc=karl.kiniger@med.ge.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@suse.de \
    --cc=t.artem@lycos.com \
    --cc=torvalds@linux-foundation.org \
    --cc=tytso@mit.edu \
    /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