From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with SMTP id 930816B004A for ; Mon, 29 Nov 2010 20:01:40 -0500 (EST) Received: from m5.gw.fujitsu.co.jp ([10.0.50.75]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id oAU11b0Z008598 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Tue, 30 Nov 2010 10:01:38 +0900 Received: from smail (m5 [127.0.0.1]) by outgoing.m5.gw.fujitsu.co.jp (Postfix) with ESMTP id 5FDBD45DE4F for ; Tue, 30 Nov 2010 10:01:37 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (s5.gw.fujitsu.co.jp [10.0.50.95]) by m5.gw.fujitsu.co.jp (Postfix) with ESMTP id 340B445DE52 for ; Tue, 30 Nov 2010 10:01:37 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id 0F9641DB8060 for ; Tue, 30 Nov 2010 10:01:37 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id 8ADF21DB803F for ; Tue, 30 Nov 2010 10:01:36 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [PATCH v3 1/3] deactivate invalidated pages In-Reply-To: <6e01d81a4b575dcaaacc6b3782c505103e024085.1291043274.git.minchan.kim@gmail.com> References: <6e01d81a4b575dcaaacc6b3782c505103e024085.1291043274.git.minchan.kim@gmail.com> Message-Id: <20101130100134.82E3.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Tue, 30 Nov 2010 10:01:35 +0900 (JST) Sender: owner-linux-mm@kvack.org To: Minchan Kim Cc: kosaki.motohiro@jp.fujitsu.com, Andrew Morton , linux-mm , LKML , Ben Gamari , Peter Zijlstra , Wu Fengguang , Johannes Weiner , Nick Piggin , Mel Gorman List-ID: > Recently, there are reported problem about thrashing. > (http://marc.info/?l=rsync&m=128885034930933&w=2) > It happens by backup workloads(ex, nightly rsync). > That's because the workload makes just use-once pages > and touches pages twice. It promotes the page into > active list so that it results in working set page eviction. > > Some app developer want to support POSIX_FADV_NOREUSE. > But other OSes don't support it, either. > (http://marc.info/?l=linux-mm&m=128928979512086&w=2) > > By other approach, app developers use POSIX_FADV_DONTNEED. > But it has a problem. If kernel meets page is writing > during invalidate_mapping_pages, it can't work. > It is very hard for application programmer to use it. > Because they always have to sync data before calling > fadivse(..POSIX_FADV_DONTNEED) to make sure the pages could > be discardable. At last, they can't use deferred write of kernel > so that they could see performance loss. > (http://insights.oetiker.ch/linux/fadvise.html) > > In fact, invalidation is very big hint to reclaimer. > It means we don't use the page any more. So let's move > the writing page into inactive list's head. > > Why I need the page to head, Dirty/Writeback page would be flushed > sooner or later. It can prevent writeout of pageout which is less > effective than flusher's writeout. > > Originally, I reused lru_demote of Peter with some change so added > his Signed-off-by. > > Reported-by: Ben Gamari > Signed-off-by: Minchan Kim > Signed-off-by: Peter Zijlstra > Acked-by: Rik van Riel > Cc: Wu Fengguang > Cc: KOSAKI Motohiro > Cc: Johannes Weiner > Cc: Nick Piggin > Cc: Mel Gorman Reviewed-by: KOSAKI Motohiro -- 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 policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org