From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755683AbYCQCpz (ORCPT ); Sun, 16 Mar 2008 22:45:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752873AbYCQCpr (ORCPT ); Sun, 16 Mar 2008 22:45:47 -0400 Received: from n6.bullet.mud.yahoo.com ([216.252.100.57]:40481 "HELO n6.bullet.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752590AbYCQCpq (ORCPT ); Sun, 16 Mar 2008 22:45:46 -0400 X-Yahoo-Newman-Id: 22876.29537.bm@omp424.mail.mud.yahoo.com DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:X-YMail-OSG:X-Yahoo-Newman-Property:From:To:Subject:Date:User-Agent:Cc:References:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-Disposition:Message-Id; b=0E/H8hVCjw2YvqsZMVbHtJ9n/yZZ98klIEkZ31JxEQgDE7F9aiExu9UwNTzaf3mqzc9rWzA1hf8ffA5c1K1eoXn/SoVOuI3lWvNdVETUvGBLn3LTFyyK091XpYQPG4DRIiSYFCNx7YS1ZzhkILK6uH6DOx3iCPKDD4lyCFa11uY= ; X-YMail-OSG: IRlcu8MVM1lW_mubNehu3KTn.Eb3fVyLq4uyIbBvOeTKlOKiASCalQxehTAu8utBMKSeRKYK5Q-- X-Yahoo-Newman-Property: ymail-3 From: Nick Piggin To: Adam Megacz Subject: Re: question about PAE and buffercache Date: Mon, 17 Mar 2008 13:27:44 +1100 User-Agent: KMail/1.9.5 Cc: linux-kernel@vger.kernel.org References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200803171327.45159.nickpiggin@yahoo.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 13 March 2008 08:48, Adam Megacz wrote: > Sorry to ask here, but I looked around for quite a while on the web. > > Is the size of the buffercache in any way constrained by the amount of > virtual memory space allocated to the kernel (when using a PAE kernel)? > > For example with a 1G/3G split and 8G of physical memory, if userspace > processes aren't interested in more than 6G of that memory, would the > kernel fully utilize all of the remaining 2G for buffercache? No. It is indeed constrained by the amount of virtual memory space the kernel has. So it could use in practice probably only around 700-800MB for buffercache.