From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id B52EA6B0087 for ; Thu, 14 May 2009 16:14:38 -0400 (EDT) Received: from localhost (smtp.ultrahosting.com [127.0.0.1]) by smtp.ultrahosting.com (Postfix) with ESMTP id AD8E282C397 for ; Thu, 14 May 2009 16:27:37 -0400 (EDT) Received: from smtp.ultrahosting.com ([74.213.175.254]) by localhost (smtp.ultrahosting.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id n5xVntCwTV0c for ; Thu, 14 May 2009 16:27:37 -0400 (EDT) Received: from qirst.com (unknown [74.213.171.31]) by smtp.ultrahosting.com (Postfix) with ESMTP id C83FF82C396 for ; Thu, 14 May 2009 16:27:32 -0400 (EDT) Date: Thu, 14 May 2009 16:14:31 -0400 (EDT) From: Christoph Lameter Subject: Re: [PATCH -mm] vmscan: protect a fraction of file backed mapped pages from reclaim In-Reply-To: <20090513084306.5874.A69D9226@jp.fujitsu.com> Message-ID: References: <20090512120002.D616.A69D9226@jp.fujitsu.com> <20090513084306.5874.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: KOSAKI Motohiro Cc: Wu Fengguang , Andrew Morton , "hannes@cmpxchg.org" , "peterz@infradead.org" , "riel@redhat.com" , "linux-kernel@vger.kernel.org" , "tytso@mit.edu" , "linux-mm@kvack.org" , "elladan@eskimo.com" , "npiggin@suse.de" , "minchan.kim@gmail.com" List-ID: On Wed, 13 May 2009, KOSAKI Motohiro wrote: > > All these expiration modifications do not take into account that a desktop > > may sit idle for hours while some other things run in the background (like > > backups at night or updatedb and other maintenance things). This still > > means that the desktop will be usuable in the morning. > > Have you seen this phenomenom? > I always use linux desktop for development. but I haven't seen it. > perhaps I have no luck. I really want to know reproduce way. > > Please let me know reproduce way. Run a backup (or rsync) over a few hundred GB. > > The percentage of file backed pages protected is set via > > /proc/sys/vm/file_mapped_ratio. This defaults to 20%. > > Why do you think typical mapped ratio is less than 20% on desktop machine? Observation of the typical mapped size of Firefox under KDE. > key point is access-once vs access-many. Nothing against it if it works. -- 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