All of lore.kernel.org
 help / color / mirror / Atom feed
From: Rik van Riel <riel@redhat.com>
To: Mel Gorman <mgorman@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Konstantin Khlebnikov <khlebnikov@openvz.org>,
	Hugh Dickins <hughd@google.com>, Ying Han <yinghan@google.com>,
	Linux-MM <linux-mm@kvack.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 0/3] Removal of lumpy reclaim V2
Date: Wed, 11 Apr 2012 14:06:11 -0400	[thread overview]
Message-ID: <4F85C813.2050206@redhat.com> (raw)
In-Reply-To: <20120411175215.GI3789@suse.de>

On 04/11/2012 01:52 PM, Mel Gorman wrote:
> On Wed, Apr 11, 2012 at 01:17:02PM -0400, Rik van Riel wrote:

>> Next step: get rid of __GFP_NO_KSWAPD for THP, first
>> in the -mm kernel
>>
>
> Initially the flag was introduced because kswapd reclaimed too
> aggressively. One would like to believe that it would be less of a problem
> now but we must avoid a situation where the CPU and reclaim cost of kswapd
> exceeds the benefit of allocating a THP.

Since kswapd and the direct reclaim code now use
the same conditionals for calling compaction,
the cost ought to be identical.

I agree this is something we should shake out
in -mm for a while though, before considering a
mainline merge.

Andrew, would you be willing to take a removal
of __GFP_NO_KSWAPD in -mm, and push it to Linus
for the 3.6 kernel if no ill effects are seen
in -mm and -next?

WARNING: multiple messages have this Message-ID (diff)
From: Rik van Riel <riel@redhat.com>
To: Mel Gorman <mgorman@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Konstantin Khlebnikov <khlebnikov@openvz.org>,
	Hugh Dickins <hughd@google.com>, Ying Han <yinghan@google.com>,
	Linux-MM <linux-mm@kvack.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 0/3] Removal of lumpy reclaim V2
Date: Wed, 11 Apr 2012 14:06:11 -0400	[thread overview]
Message-ID: <4F85C813.2050206@redhat.com> (raw)
In-Reply-To: <20120411175215.GI3789@suse.de>

On 04/11/2012 01:52 PM, Mel Gorman wrote:
> On Wed, Apr 11, 2012 at 01:17:02PM -0400, Rik van Riel wrote:

>> Next step: get rid of __GFP_NO_KSWAPD for THP, first
>> in the -mm kernel
>>
>
> Initially the flag was introduced because kswapd reclaimed too
> aggressively. One would like to believe that it would be less of a problem
> now but we must avoid a situation where the CPU and reclaim cost of kswapd
> exceeds the benefit of allocating a THP.

Since kswapd and the direct reclaim code now use
the same conditionals for calling compaction,
the cost ought to be identical.

I agree this is something we should shake out
in -mm for a while though, before considering a
mainline merge.

Andrew, would you be willing to take a removal
of __GFP_NO_KSWAPD in -mm, and push it to Linus
for the 3.6 kernel if no ill effects are seen
in -mm and -next?

--
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/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2012-04-11 18:56 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-04-11 16:38 [PATCH 0/3] Removal of lumpy reclaim V2 Mel Gorman
2012-04-11 16:38 ` Mel Gorman
2012-04-11 16:38 ` [PATCH 1/3] mm: vmscan: Remove lumpy reclaim Mel Gorman
2012-04-11 16:38   ` Mel Gorman
2012-04-11 17:25   ` Rik van Riel
2012-04-11 17:25     ` Rik van Riel
2012-04-11 18:54     ` KOSAKI Motohiro
2012-04-11 18:54       ` KOSAKI Motohiro
2012-04-11 16:38 ` [PATCH 2/3] mm: vmscan: Do not stall on writeback during memory compaction Mel Gorman
2012-04-11 16:38   ` Mel Gorman
2012-04-11 17:26   ` Rik van Riel
2012-04-11 17:26     ` Rik van Riel
2012-04-11 18:51     ` KOSAKI Motohiro
2012-04-11 18:51       ` KOSAKI Motohiro
2012-04-11 16:38 ` [PATCH 3/3] mm: vmscan: Remove reclaim_mode_t Mel Gorman
2012-04-11 16:38   ` Mel Gorman
2012-04-11 17:26   ` Rik van Riel
2012-04-11 17:26     ` Rik van Riel
2012-04-11 19:48     ` KOSAKI Motohiro
2012-04-11 19:48       ` KOSAKI Motohiro
2012-04-11 17:17 ` [PATCH 0/3] Removal of lumpy reclaim V2 Rik van Riel
2012-04-11 17:17   ` Rik van Riel
2012-04-11 17:52   ` Mel Gorman
2012-04-11 17:52     ` Mel Gorman
2012-04-11 18:06     ` Rik van Riel [this message]
2012-04-11 18:06       ` Rik van Riel
2012-04-12  9:32       ` Mel Gorman
2012-04-12  9:32         ` Mel Gorman
2012-04-11 23:37 ` Ying Han
2012-04-11 23:37   ` Ying Han
2012-04-12  5:49   ` Mel Gorman
2012-04-12  5:49     ` Mel Gorman
2012-04-11 23:54 ` Hugh Dickins
2012-04-11 23:54   ` Hugh Dickins
2012-04-12  5:44   ` Mel Gorman
2012-04-12  5:44     ` Mel Gorman

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=4F85C813.2050206@redhat.com \
    --to=riel@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=hughd@google.com \
    --cc=khlebnikov@openvz.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@suse.de \
    --cc=yinghan@google.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 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.