Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752799Ab0LEFOT (ORCPT ); Sun, 5 Dec 2010 00:14:19 -0500 Received: from e23smtp09.au.ibm.com ([202.81.31.142]:37223 "EHLO e23smtp09.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750743Ab0LEFOR (ORCPT ); Sun, 5 Dec 2010 00:14:17 -0500 Date: Thu, 2 Dec 2010 12:31:04 +0530 From: Balbir Singh To: KAMEZAWA Hiroyuki Cc: KOSAKI Motohiro , Christoph Lameter , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kvm Subject: Re: [PATCH 3/3] Provide control over unmapped pages Message-ID: <20101202070103.GP2746@balbir.in.ibm.com> Reply-To: balbir@linux.vnet.ibm.com References: <20101130142509.4f49d452.akpm@linux-foundation.org> <20101202102110.157F.A69D9226@jp.fujitsu.com> <20101202115036.1a4a42b5.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20101202115036.1a4a42b5.kamezawa.hiroyu@jp.fujitsu.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1841 Lines: 47 * KAMEZAWA Hiroyuki [2010-12-02 11:50:36]: > On Thu, 2 Dec 2010 10:22:16 +0900 (JST) > KOSAKI Motohiro wrote: > > > > On Tue, 30 Nov 2010, Andrew Morton wrote: > > > > > > > > +#define UNMAPPED_PAGE_RATIO 16 > > > > > > > > Well. Giving 16 a name didn't really clarify anything. Attentive > > > > readers will want to know what this does, why 16 was chosen and what > > > > the effects of changing it will be. > > > > > > The meaning is analoguous to the other zone reclaim ratio. But yes it > > > should be justified and defined. > > > > > > > > Reviewed-by: Christoph Lameter > > > > > > > > So you're OK with shoving all this flotsam into 100,000,000 cellphones? > > > > This was a pretty outrageous patchset! > > > > > > This is a feature that has been requested over and over for years. Using > > > /proc/vm/drop_caches for fixing situations where one simply has too many > > > page cache pages is not so much fun in the long run. > > > > I'm not against page cache limitation feature at all. But, this is > > too ugly and too destructive fast path. I hope this patch reduce negative > > impact more. > > > > And I think min_mapped_unmapped_pages is ugly. It should be > "unmapped_pagecache_limit" or some because it's for limitation feature. > The feature will now be enabled with a CONFIG and boot parameter, I find changing the naming convention now - it is already in use and well known is not a good idea. THe name of the boot parameter can be changed of-course. -- Three Cheers, Balbir -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/