Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753668AbZJAPIa (ORCPT ); Thu, 1 Oct 2009 11:08:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752972AbZJAPIa (ORCPT ); Thu, 1 Oct 2009 11:08:30 -0400 Received: from smtp2.ultrahosting.com ([74.213.174.253]:52511 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752194AbZJAPI3 (ORCPT ); Thu, 1 Oct 2009 11:08:29 -0400 Date: Thu, 1 Oct 2009 11:03:16 -0400 (EDT) From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Mel Gorman cc: Pekka Enberg , Nick Piggin , heiko.carstens@de.ibm.com, sachinp@in.ibm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Tejun Heo , Benjamin Herrenschmidt Subject: Re: [PATCH 2/4] slqb: Record what node is local to a kmem_cache_cpu In-Reply-To: <20091001150346.GD21906@csn.ul.ie> Message-ID: References: <84144f020909220638l79329905sf9a35286130e88d0@mail.gmail.com> <20090922135453.GF25965@csn.ul.ie> <84144f020909221154x820b287r2996480225692fad@mail.gmail.com> <20090922185608.GH25965@csn.ul.ie> <20090930144117.GA17906@csn.ul.ie> <20090930220541.GA31530@csn.ul.ie> <20091001104046.GA21906@csn.ul.ie> <20091001150346.GD21906@csn.ul.ie> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 989 Lines: 20 On Thu, 1 Oct 2009, Mel Gorman wrote: > True, it might have been improved more if SLUB knew what local hugepage it > resided within as the kernel portion of the address space is backed by huge > TLB entries. Note that SLQB could have an advantage here early in boot as > the page allocator will tend to give it back pages within a single huge TLB > entry. It loses the advantage when the system has been running for a very long > time but it might be enough to skew benchmark results on cold-booted systems. The page allocator serves pages aligned to huge page boundaries as far as I can remember. You can actually use huge pages in slub if you set the max order to 9. So a page obtained from the page allocator is always aligned properly. -- 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/