From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with SMTP id 4ED456B0071 for ; Tue, 12 Jan 2010 18:40:36 -0500 (EST) Received: from m4.gw.fujitsu.co.jp ([10.0.50.74]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o0CNeXb3007153 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Wed, 13 Jan 2010 08:40:34 +0900 Received: from smail (m4 [127.0.0.1]) by outgoing.m4.gw.fujitsu.co.jp (Postfix) with ESMTP id BD36A45DE6E for ; Wed, 13 Jan 2010 08:40:33 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (s4.gw.fujitsu.co.jp [10.0.50.94]) by m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 9928945DE60 for ; Wed, 13 Jan 2010 08:40:33 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 6848C1DB803E for ; Wed, 13 Jan 2010 08:40:33 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 198F71DB803B for ; Wed, 13 Jan 2010 08:40:33 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [PATCH -mmotm-2010-01-06-14-34] check high watermark after shrink zone In-Reply-To: <20100112150152.78604b78.akpm@linux-foundation.org> References: <20100108141235.ef56b567.minchan.kim@barrios-desktop> <20100112150152.78604b78.akpm@linux-foundation.org> Message-Id: <20100113083339.B3C5.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Wed, 13 Jan 2010 08:40:32 +0900 (JST) Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: kosaki.motohiro@jp.fujitsu.com, Minchan Kim , Mel Gorman , Rik van Riel , linux-mm , lkml List-ID: > > mm/vmscan.c | 21 +++++++++++---------- > > 1 files changed, 11 insertions(+), 10 deletions(-) > > > > diff --git a/mm/vmscan.c b/mm/vmscan.c > > index 885207a..b81adf8 100644 > > --- a/mm/vmscan.c > > +++ b/mm/vmscan.c > > @@ -2057,9 +2057,6 @@ loop_again: > > priority != DEF_PRIORITY) > > continue; > > > > - if (!zone_watermark_ok(zone, order, > > - high_wmark_pages(zone), end_zone, 0)) > > - all_zones_ok = 0; > > This will make kswapd stop doing reclaim if all zones have > zone_is_all_unreclaimable(): > > if (zone_is_all_unreclaimable(zone)) > continue; > > This seems bad. No. That's intentional, I think. All zones of small asymmetric numa node are always unreclaimable typically. stopping kswapd prevent to waste 100% cpu time such situation. In the other hand, This logic doesn't cause disaster to symmetric numa. it merely cause direct reclaim and re-wakeup kswapd. -- 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