From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752420AbZDWBVI (ORCPT ); Wed, 22 Apr 2009 21:21:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751432AbZDWBUw (ORCPT ); Wed, 22 Apr 2009 21:20:52 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:56360 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751110AbZDWBUv (ORCPT ); Wed, 22 Apr 2009 21:20:51 -0400 From: KOSAKI Motohiro To: Mel Gorman , Andrew Morton Subject: Re: [PATCH] low order lumpy reclaim also should use PAGEOUT_IO_SYNC. Cc: kosaki.motohiro@jp.fujitsu.com, Andy Whitcroft , Peter Zijlstra , Rik van Riel , LKML , linux-mm , Lee Schermerhorn In-Reply-To: <20090422143201.GE15367@csn.ul.ie> References: <20090421142056.F127.A69D9226@jp.fujitsu.com> <20090422143201.GE15367@csn.ul.ie> Message-Id: <20090423094411.F6EC.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.50 [ja] Date: Thu, 23 Apr 2009 10:20:47 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Tue, Apr 21, 2009 at 02:22:27PM +0900, KOSAKI Motohiro wrote: > > Subject: [PATCH] low order lumpy reclaim also should use PAGEOUT_IO_SYNC. > > > > commit 33c120ed2843090e2bd316de1588b8bf8b96cbde (more aggressively use lumpy reclaim) > > change lumpy reclaim using condition. but it isn't enough change. > > > > lumpy reclaim don't only mean isolate neighber page, but also do pageout as synchronous. > > this patch does it. > > > > Cc: Lee Schermerhorn > > Cc: Andy Whitcroft > > Cc: Peter Zijlstra > > Cc: Mel Gorman > > Cc: Rik van Riel > > Signed-off-by: KOSAKI Motohiro > > Seems fair although the changelog could be better. Maybe something like? > > ==== > > Commit 33c120ed2843090e2bd316de1588b8bf8b96cbde increased how aggressive > lumpy reclaim was by isolating both active and inactive pages for asynchronous > lumpy reclaim on costly-high-order pages and for cheap-high-order when memory > pressure is high. However, if the system is under heavy pressure and there > are dirty pages, asynchronous IO may not be sufficient to reclaim a suitable > page in time. > > This patch causes the caller to enter synchronous lumpy reclaim for > costly-high-order pages and for cheap-high-order pages when under memory > pressure. > ==== > > Whether the changelog is updated or not though; > > Reviewed-by: Mel Gorman Cool! Andrew, Could you please replace vmscan-low-order-lumpy-reclaim-also-should-use-pageout_io_sync.patch with following patch? =================================== Subject: vmscan: low order lumpy reclaim also should use PAGEOUT_IO_SYNC From: KOSAKI Motohiro Commit 33c120ed2843090e2bd316de1588b8bf8b96cbde increased how aggressive lumpy reclaim was by isolating both active and inactive pages for asynchronous lumpy reclaim on costly-high-order pages and for cheap-high-order when memory pressure is high. However, if the system is under heavy pressure and there are dirty pages, asynchronous IO may not be sufficient to reclaim a suitable page in time. This patch causes the caller to enter synchronous lumpy reclaim for costly-high-order pages and for cheap-high-order pages when under memory pressure. Minchan.kim@gmail.com said: Andy added synchronous lumpy reclaim with c661b078fd62abe06fd11fab4ac5e4eeafe26b6d. At that time, lumpy reclaim is not agressive. His intension is just for high-order users.(above PAGE_ALLOC_COSTLY_ORDER). After some time, Rik added aggressive lumpy reclaim with 33c120ed2843090e2bd316de1588b8bf8b96cbde. His intention was to do lumpy reclaim when high-order users and trouble getting a small set of contiguous pages. So we also have to add synchronous pageout for small set of contiguous pages. Cc: Lee Schermerhorn Cc: Andy Whitcroft Cc: Peter Zijlstra Cc: Rik van Riel Signed-off-by: KOSAKI Motohiro Reviewed-by: Minchan Kim Reviewed-by: Mel Gorman Signed-off-by: Andrew Morton --- mm/vmscan.c | 29 +++++++++++++++-------------- 1 file changed, 15 insertions(+), 14 deletions(-) diff -puN mm/vmscan.c~vmscan-low-order-lumpy-reclaim-also-should-use-pageout_io_sync mm/vmscan.c --- a/mm/vmscan.c~vmscan-low-order-lumpy-reclaim-also-should-use-pageout_io_sync +++ a/mm/vmscan.c @@ -1059,6 +1059,19 @@ static unsigned long shrink_inactive_lis unsigned long nr_scanned = 0; unsigned long nr_reclaimed = 0; struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); + int lumpy_reclaim = 0; + + /* + * If we need a large contiguous chunk of memory, or have + * trouble getting a small set of contiguous pages, we + * will reclaim both active and inactive pages. + * + * We use the same threshold as pageout congestion_wait below. + */ + if (sc->order > PAGE_ALLOC_COSTLY_ORDER) + lumpy_reclaim = 1; + else if (sc->order && priority < DEF_PRIORITY - 2) + lumpy_reclaim = 1; pagevec_init(&pvec, 1); @@ -1071,19 +1084,7 @@ static unsigned long shrink_inactive_lis unsigned long nr_freed; unsigned long nr_active; unsigned int count[NR_LRU_LISTS] = { 0, }; - int mode = ISOLATE_INACTIVE; - - /* - * If we need a large contiguous chunk of memory, or have - * trouble getting a small set of contiguous pages, we - * will reclaim both active and inactive pages. - * - * We use the same threshold as pageout congestion_wait below. - */ - if (sc->order > PAGE_ALLOC_COSTLY_ORDER) - mode = ISOLATE_BOTH; - else if (sc->order && priority < DEF_PRIORITY - 2) - mode = ISOLATE_BOTH; + int mode = lumpy_reclaim ? ISOLATE_BOTH : ISOLATE_INACTIVE; nr_taken = sc->isolate_pages(sc->swap_cluster_max, &page_list, &nr_scan, sc->order, mode, @@ -1120,7 +1121,7 @@ static unsigned long shrink_inactive_lis * but that should be acceptable to the caller */ if (nr_freed < nr_taken && !current_is_kswapd() && - sc->order > PAGE_ALLOC_COSTLY_ORDER) { + lumpy_reclaim) { congestion_wait(WRITE, HZ/10); /* _