Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764722AbYCGEhY (ORCPT ); Thu, 6 Mar 2008 23:37:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755384AbYCGEhF (ORCPT ); Thu, 6 Mar 2008 23:37:05 -0500 Received: from mx2.suse.de ([195.135.220.15]:55604 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758159AbYCGEhE (ORCPT ); Thu, 6 Mar 2008 23:37:04 -0500 Date: Fri, 7 Mar 2008 05:37:00 +0100 From: Nick Piggin To: Christoph Lameter Cc: netdev@vger.kernel.org, Linux Kernel Mailing List , yanmin_zhang@linux.intel.com, David Miller , Eric Dumazet Subject: Re: [rfc][patch 2/3] slab: introduce SMP alignment Message-ID: <20080307043700.GI21185@wotan.suse.de> References: <20080303093449.GA15091@wotan.suse.de> <20080303093529.GB15091@wotan.suse.de> <20080303200355.GB8974@wotan.suse.de> <20080303201211.GE8974@wotan.suse.de> <20080303202411.GH8974@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 971 Lines: 21 On Mon, Mar 03, 2008 at 01:31:14PM -0800, Christoph Lameter wrote: > On Mon, 3 Mar 2008, Nick Piggin wrote: > > > And maybe the VSMP guys will want to blow this out to their internode > > alignment? > > > > max(!CONFIG_TINY && num_possible_cpus() > 1 ? (is_vsmp ? internode_alignemnt : cache_line_size()) : 0, mandatory_alignment) > > No the slab allocators were optimized for VSMP so that the > internode_alignment is not necessary there. That was actually one of the > requirements that triggered the slab numa work. BTW. can you explain this incredible claim that the slab allocators do not need internode_alignment to avoid false sharing of allocated objects on VSMP? I don't understand how that would work at all. -- 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/