From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758867AbYD2N2P (ORCPT ); Tue, 29 Apr 2008 09:28:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755434AbYD2N17 (ORCPT ); Tue, 29 Apr 2008 09:27:59 -0400 Received: from smtp-out.google.com ([216.239.33.17]:24088 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755158AbYD2N17 (ORCPT ); Tue, 29 Apr 2008 09:27:59 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=received:message-id:date:from:to:subject:cc:in-reply-to: mime-version:content-type:content-transfer-encoding: content-disposition:references; b=x7RsowEj5xvD4u9pSEnlLwdm/IjUhXrzPxcXfYDiTKGyvfI4qp0AebpkbEvyC2ZoY /0JVeqJ+bhBTQrf9P3xuw== Message-ID: Date: Tue, 29 Apr 2008 09:27:53 -0400 From: "Ross Biro" To: "Christoph Lameter" Subject: Re: [PATCH 1/2] MM: Make page tables relocatable -- conditional flush (rc9) Cc: "Andrew Morton" , linux-kernel@vger.kernel.org, linux-mm@kvack.org, mel@skynet.ie, apm@shadoween.org In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080414163933.A9628DCA48@localhost> <20080414155702.ca7eb622.akpm@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 16, 2008 at 3:22 PM, Christoph Lameter wrote: > The patch is interesting because it would allow the moving of page table > pages into MOVABLE sections and reduce the size of the UNMOVABLE > allocations signficantly (Ross: We need some numbers here). This in turn Is there a standard test used to evaluate kernel memory fragmentation? I'm sure I can rig up a test to create huge amounts of fragmentation with about 1/2 the pages being page tables. However, I doubt that it would reflect any real loads. Similarly, if I check the memory fragmentation on my test system right after it's been booted, I won't see much fragmentation and page tables won't be causing any trouble. Ross