linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andrea Righi <arighi@develer.com>,
	Balbir Singh <balbir@linux.vnet.ibm.com>,
	Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>,
	Vivek Goyal <vgoyal@redhat.com>,
	Trond Myklebust <trond.myklebust@fys.uio.no>,
	Suleiman Souhlal <suleiman@google.com>,
	Greg Thelen <gthelen@google.com>,
	"Kirill A. Shutemov" <kirill@shutemov.name>,
	Andrew Morton <akpm@linux-foundation.org>,
	containers@lists.linux-foundation.org,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH -mmotm 0/5] memcg: per cgroup dirty limit (v6)
Date: Thu, 11 Mar 2010 10:14:25 +0100	[thread overview]
Message-ID: <1268298865.5279.997.camel@twins> (raw)
In-Reply-To: <20100311101726.f58d24e9.kamezawa.hiroyu@jp.fujitsu.com>

On Thu, 2010-03-11 at 10:17 +0900, KAMEZAWA Hiroyuki wrote:
> On Thu, 11 Mar 2010 09:39:13 +0900
> KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> wrote:
> > > The performance overhead is not so huge in both solutions, but the impact on
> > > performance is even more reduced using a complicated solution...
> > > 
> > > Maybe we can go ahead with the simplest implementation for now and start to
> > > think to an alternative implementation of the page_cgroup locking and
> > > charge/uncharge of pages.

FWIW bit spinlocks suck massive.

> > 
> > maybe. But in this 2 years, one of our biggest concerns was the performance.
> > So, we do something complex in memcg. But complex-locking is , yes, complex.
> > Hmm..I don't want to bet we can fix locking scheme without something complex.
> > 
> But overall patch set seems good (to me.) And dirty_ratio and dirty_background_ratio
> will give us much benefit (of performance) than we lose by small overheads.

Well, the !cgroup or root case should really have no performance impact.

> IIUC, this series affects trgger for background-write-out.

Not sure though, while this does the accounting the actual writeout is
still !cgroup aware and can definately impact performance negatively by
shrinking too much.

--
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:[~2010-03-11  9:14 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-09 23:00 [PATCH -mmotm 0/5] memcg: per cgroup dirty limit (v6) Andrea Righi
2010-03-09 23:00 ` [PATCH -mmotm 1/5] memcg: disable irq at page cgroup lock Andrea Righi
2010-03-09 23:00 ` [PATCH -mmotm 2/5] memcg: dirty memory documentation Andrea Righi
2010-03-09 23:00 ` [PATCH -mmotm 3/5] page_cgroup: introduce file cache flags Andrea Righi
2010-03-09 23:00 ` [PATCH -mmotm 4/5] memcg: dirty pages accounting and limiting infrastructure Andrea Righi
2010-03-10 22:23   ` Vivek Goyal
2010-03-11 22:27     ` Andrea Righi
2010-03-09 23:00 ` [PATCH -mmotm 5/5] memcg: dirty pages instrumentation Andrea Righi
2010-03-10  1:36 ` [PATCH -mmotm 0/5] memcg: per cgroup dirty limit (v6) Balbir Singh
2010-03-11  0:39 ` KAMEZAWA Hiroyuki
2010-03-11  1:17   ` KAMEZAWA Hiroyuki
2010-03-11  9:14     ` Peter Zijlstra [this message]
2010-03-11  9:25       ` KAMEZAWA Hiroyuki
2010-03-11  9:42         ` KAMEZAWA Hiroyuki
2010-03-11 22:20           ` Andrea Righi
2010-03-12  1:14           ` Daisuke Nishimura
2010-03-12  2:24             ` KAMEZAWA Hiroyuki
2010-03-15 14:48               ` Vivek Goyal
2010-03-12 10:07             ` Andrea Righi
2010-03-11 15:03         ` Vivek Goyal
2010-03-11 23:27           ` Andrea Righi
2010-03-11 23:52             ` KAMEZAWA Hiroyuki
2010-03-12 10:01               ` Andrea Righi
2010-03-15 14:16             ` Vivek Goyal
2010-03-11 23:42           ` KAMEZAWA Hiroyuki
2010-03-12  0:33             ` Andrea Righi
2010-03-15 14:38             ` Vivek Goyal
2010-03-17 22:32               ` Andrea Righi
2010-03-11 22:23   ` Andrea Righi
2010-03-11 18:07 ` Vivek Goyal
2010-03-11 23:59   ` Andrea Righi
2010-03-12  0:03     ` KAMEZAWA Hiroyuki
2010-03-12  9:58       ` Andrea Righi
2010-03-15 14:41     ` Vivek Goyal

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=1268298865.5279.997.camel@twins \
    --to=peterz@infradead.org \
    --cc=akpm@linux-foundation.org \
    --cc=arighi@develer.com \
    --cc=balbir@linux.vnet.ibm.com \
    --cc=containers@lists.linux-foundation.org \
    --cc=gthelen@google.com \
    --cc=kamezawa.hiroyu@jp.fujitsu.com \
    --cc=kirill@shutemov.name \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=nishimura@mxp.nes.nec.co.jp \
    --cc=suleiman@google.com \
    --cc=trond.myklebust@fys.uio.no \
    --cc=vgoyal@redhat.com \
    /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).