All of lore.kernel.org
 help / color / mirror / Atom feed
From: Rik van Riel <riel@redhat.com>
To: Christoph Lameter <cl@linux-foundation.org>
Cc: Robin Holt <holt@sgi.com>,
	KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
	LKML <linux-kernel@vger.kernel.org>,
	linux-mm <linux-mm@kvack.org>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 4/4] zone_reclaim_mode is always 0 by default
Date: Thu, 14 May 2009 16:23:18 -0400	[thread overview]
Message-ID: <4A0C7DB6.6010601@redhat.com> (raw)
In-Reply-To: <alpine.DEB.1.10.0905141602010.1381@qirst.com>

Christoph Lameter wrote:
> Not having zone reclaim on a NUMA system often means that per node
> allocations will fall back. Optimized node local allocations become very
> difficult for the page allocator. If the latency penalties are not
> significant then this may not matter. The larger the system, the larger
> the NUMA latencies become.
> 
> One possibility would be to disable zone reclaim for low node numbers.
> Eanble it only if more than 4 nodes exist?

I suspect that patches 1/4 through 3/4 will cause the
system to behave better already, by only reclaiming
the easiest to reclaim pages from zone reclaim and
falling back after that - or am overlooking something?

WARNING: multiple messages have this Message-ID (diff)
From: Rik van Riel <riel@redhat.com>
To: Christoph Lameter <cl@linux-foundation.org>
Cc: Robin Holt <holt@sgi.com>,
	KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
	LKML <linux-kernel@vger.kernel.org>,
	linux-mm <linux-mm@kvack.org>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 4/4] zone_reclaim_mode is always 0 by default
Date: Thu, 14 May 2009 16:23:18 -0400	[thread overview]
Message-ID: <4A0C7DB6.6010601@redhat.com> (raw)
In-Reply-To: <alpine.DEB.1.10.0905141602010.1381@qirst.com>

Christoph Lameter wrote:
> Not having zone reclaim on a NUMA system often means that per node
> allocations will fall back. Optimized node local allocations become very
> difficult for the page allocator. If the latency penalties are not
> significant then this may not matter. The larger the system, the larger
> the NUMA latencies become.
> 
> One possibility would be to disable zone reclaim for low node numbers.
> Eanble it only if more than 4 nodes exist?

I suspect that patches 1/4 through 3/4 will cause the
system to behave better already, by only reclaiming
the easiest to reclaim pages from zone reclaim and
falling back after that - or am overlooking something?

--
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:[~2009-05-14 20:23 UTC|newest]

Thread overview: 90+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-05-13  3:06 [PATCH 0/4] various zone_reclaim cleanup KOSAKI Motohiro
2009-05-13  3:06 ` KOSAKI Motohiro
2009-05-13  3:06 ` [PATCH 1/4] vmscan: change the number of the unmapped files in zone reclaim KOSAKI Motohiro
2009-05-13  3:06   ` KOSAKI Motohiro
2009-05-13 13:31   ` Rik van Riel
2009-05-13 13:31     ` Rik van Riel
2009-05-14 19:52   ` Christoph Lameter
2009-05-14 19:52     ` Christoph Lameter
2009-05-18  3:15   ` Wu Fengguang
2009-05-18  3:15     ` Wu Fengguang
2009-05-18  3:35     ` KOSAKI Motohiro
2009-05-18  3:35       ` KOSAKI Motohiro
2009-05-18  3:53       ` Wu Fengguang
2009-05-18  3:53         ` Wu Fengguang
2009-05-19  1:11         ` KOSAKI Motohiro
2009-05-19  1:11           ` KOSAKI Motohiro
2009-05-13  3:06 ` [PATCH 2/4] vmscan: drop PF_SWAPWRITE from zone_reclaim KOSAKI Motohiro
2009-05-13  3:06   ` KOSAKI Motohiro
2009-05-13 13:35   ` Rik van Riel
2009-05-13 13:35     ` Rik van Riel
2009-05-14 19:57   ` Christoph Lameter
2009-05-14 19:57     ` Christoph Lameter
2009-05-18  3:33   ` Wu Fengguang
2009-05-18  3:33     ` Wu Fengguang
2009-05-13  3:07 ` [PATCH 3/4] vmscan: zone_reclaim use may_swap KOSAKI Motohiro
2009-05-13  3:07   ` KOSAKI Motohiro
2009-05-13 11:26   ` Johannes Weiner
2009-05-13 11:26     ` Johannes Weiner
2009-05-13 14:43   ` Rik van Riel
2009-05-13 14:43     ` Rik van Riel
2009-05-14 19:59   ` Christoph Lameter
2009-05-14 19:59     ` Christoph Lameter
2009-05-18  3:35   ` Wu Fengguang
2009-05-18  3:35     ` Wu Fengguang
2009-05-13  3:08 ` [PATCH 4/4] zone_reclaim_mode is always 0 by default KOSAKI Motohiro
2009-05-13  3:08   ` KOSAKI Motohiro
2009-05-13 14:47   ` Rik van Riel
2009-05-13 14:47     ` Rik van Riel
2009-05-14  8:20     ` KOSAKI Motohiro
2009-05-14  8:20       ` KOSAKI Motohiro
2009-05-14 11:48       ` Robin Holt
2009-05-14 11:48         ` Robin Holt
2009-05-14 12:02         ` KOSAKI Motohiro
2009-05-14 12:02           ` KOSAKI Motohiro
2009-05-13 15:22   ` Robin Holt
2009-05-13 15:22     ` Robin Holt
2009-05-14 20:05     ` Christoph Lameter
2009-05-14 20:05       ` Christoph Lameter
2009-05-14 20:23       ` Rik van Riel [this message]
2009-05-14 20:23         ` Rik van Riel
2009-05-14 20:31         ` Christoph Lameter
2009-05-14 20:31           ` Christoph Lameter
2009-05-15  1:02       ` KOSAKI Motohiro
2009-05-15  1:02         ` KOSAKI Motohiro
2009-05-15 10:51         ` Robin Holt
2009-05-15 10:51           ` Robin Holt
2009-05-19  2:53           ` KOSAKI Motohiro
2009-05-19  2:53             ` KOSAKI Motohiro
2009-05-20 14:00             ` Robin Holt
2009-05-20 14:00               ` Robin Holt
2009-05-21  2:44               ` KOSAKI Motohiro
2009-05-21  2:44                 ` KOSAKI Motohiro
2009-05-21 13:31                 ` Christoph Lameter
2009-05-21 13:31                   ` Christoph Lameter
2009-05-21 13:57                   ` Robin Holt
2009-05-21 13:57                     ` Robin Holt
2009-05-24 13:44                   ` KOSAKI Motohiro
2009-05-24 13:44                     ` KOSAKI Motohiro
2009-05-15 18:01         ` Christoph Lameter
2009-05-15 18:01           ` Christoph Lameter
2009-05-18  3:49   ` Wu Fengguang
2009-05-18  3:49     ` Wu Fengguang
2009-05-19  1:16     ` Zhang, Yanmin
2009-05-19  1:16       ` Zhang, Yanmin
2009-05-19  2:53     ` KOSAKI Motohiro
2009-05-19  2:53       ` KOSAKI Motohiro
2009-05-19  2:57       ` KOSAKI Motohiro
2009-05-19  2:57         ` KOSAKI Motohiro
2009-05-19  3:38       ` Zhang, Yanmin
2009-05-19  3:38         ` Zhang, Yanmin
2009-05-19  4:30         ` KOSAKI Motohiro
2009-05-19  4:30           ` KOSAKI Motohiro
2009-05-19  5:06           ` Zhang, Yanmin
2009-05-19  5:06             ` Zhang, Yanmin
2009-05-19  7:09             ` KOSAKI Motohiro
2009-05-19  7:09               ` KOSAKI Motohiro
2009-05-19  7:15               ` Zhang, Yanmin
2009-05-19  7:15                 ` Zhang, Yanmin
2009-05-18  9:09   ` Wu Fengguang
2009-05-18  9:09     ` Wu Fengguang

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=4A0C7DB6.6010601@redhat.com \
    --to=riel@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=cl@linux-foundation.org \
    --cc=holt@sgi.com \
    --cc=kosaki.motohiro@jp.fujitsu.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.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.