From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id 0F0D66B01C9 for ; Wed, 24 Mar 2010 06:57:30 -0400 (EDT) Date: Wed, 24 Mar 2010 10:57:08 +0000 From: Mel Gorman Subject: Re: [PATCH 07/11] Memory compaction core Message-ID: <20100324105707.GC21147@csn.ul.ie> References: <1269347146-7461-1-git-send-email-mel@csn.ul.ie> <1269347146-7461-8-git-send-email-mel@csn.ul.ie> <20100324100334.8d6f0739.kamezawa.hiroyu@jp.fujitsu.com> <28c262361003231847q1e4b7c7agdf82c4b2e920ada4@mail.gmail.com> <20100324105311.2f41e82b.kamezawa.hiroyu@jp.fujitsu.com> <28c262361003231910w27dbe52fqe02afad2b0238c9a@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <28c262361003231910w27dbe52fqe02afad2b0238c9a@mail.gmail.com> Sender: owner-linux-mm@kvack.org To: Minchan Kim Cc: KAMEZAWA Hiroyuki , Andrew Morton , Andrea Arcangeli , Christoph Lameter , Adam Litke , Avi Kivity , David Rientjes , KOSAKI Motohiro , Rik van Riel , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Wed, Mar 24, 2010 at 11:10:14AM +0900, Minchan Kim wrote: > On Wed, Mar 24, 2010 at 10:53 AM, KAMEZAWA Hiroyuki > wrote: > > On Wed, 24 Mar 2010 10:47:41 +0900 > > Minchan Kim wrote: > > > >> On Wed, Mar 24, 2010 at 10:03 AM, KAMEZAWA Hiroyuki > >> wrote: > >> > On Tue, 23 Mar 2010 12:25:42 +0000 > >> > Mel Gorman wrote: > >> > > >> >> This patch is the core of a mechanism which compacts memory in a zone by > >> >> relocating movable pages towards the end of the zone. > >> >> > >> >> A single compaction run involves a migration scanner and a free scanner. > >> >> Both scanners operate on pageblock-sized areas in the zone. The migration > >> >> scanner starts at the bottom of the zone and searches for all movable pages > >> >> within each area, isolating them onto a private list called migratelist. > >> >> The free scanner starts at the top of the zone and searches for suitable > >> >> areas and consumes the free pages within making them available for the > >> >> migration scanner. The pages isolated for migration are then migrated to > >> >> the newly isolated free pages. > >> >> > >> >> Signed-off-by: Mel Gorman > >> >> Acked-by: Rik van Riel > >> >> Reviewed-by: Minchan Kim > >> > > >> > I think lru_add_drain() or lru_add_drain_all() should be called somewhere > >> > when we do __isolate_lru_page(). But it's (_all is) slow.... > >> > > >> > >> migrate_prep does it. > >> Yep. > > Thanks. > > > > Hmm...then, lru_add_drain_all() is called at each (32page migrate) itelation. > > Isn't it too slow to be called in such frequency ? > > I agree. We can move migrate_prep in compact_zone. > Indeed we can. It's moved now. Thanks -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- 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: email@kvack.org