public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Rik van Riel <riel@redhat.com>
To: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Elladan <elladan@eskimo.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Lee Schermerhorn <lee.schermerhorn@hp.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	epasch@de.ibm.com, Martin Schwidefsky <schwidefsky@de.ibm.com>,
	Heiko Carstens <heiko.carstens@de.ibm.com>
Subject: Re: Increased Buffers due to patch 56e49d (vmscan: evict use-once pages first), but why exactly?
Date: Tue, 08 Dec 2009 11:13:59 -0500	[thread overview]
Message-ID: <4B1E7B47.1000707@redhat.com> (raw)
In-Reply-To: <4B1E76C9.50901@linux.vnet.ibm.com>

On 12/08/2009 10:54 AM, Christian Ehrhardt wrote:

> btw thanks for the explanation Rik, the file/blockdev association was
> exactly what I was missing in my thoughts.
> While my question was more intended to ask where in code these
> differentiation is made I'm perfectly fine with having it just working
> knowing that file/blockdev association is the key.

Actually, the file/blockdev association is just a coincidence,
due to the way your benchmark works.

The key is "page touched once" vs "page touched multiple times".

In eg. a database workload, I would expect much more file data
to be on the active list.  Specifically the file data corresponding
to the database indexes.

-- 
All rights reversed.

      reply	other threads:[~2009-12-08 16:16 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-12-07 14:36 Increased Buffers due to patch 56e49d (vmscan: evict use-once pages first), but why exactly? Christian Ehrhardt
2009-12-07 18:17 ` Rik van Riel
2009-12-08  0:43   ` KOSAKI Motohiro
2009-12-08 15:54     ` Christian Ehrhardt
2009-12-08 16:13       ` Rik van Riel [this message]

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=4B1E7B47.1000707@redhat.com \
    --to=riel@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=ehrhardt@linux.vnet.ibm.com \
    --cc=elladan@eskimo.com \
    --cc=epasch@de.ibm.com \
    --cc=hannes@cmpxchg.org \
    --cc=heiko.carstens@de.ibm.com \
    --cc=kosaki.motohiro@jp.fujitsu.com \
    --cc=lee.schermerhorn@hp.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=peterz@infradead.org \
    --cc=schwidefsky@de.ibm.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