Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762527AbYCGCVU (ORCPT ); Thu, 6 Mar 2008 21:21:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756865AbYCGCU7 (ORCPT ); Thu, 6 Mar 2008 21:20:59 -0500 Received: from relay2.sgi.com ([192.48.171.30]:60316 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756834AbYCGCU6 (ORCPT ); Thu, 6 Mar 2008 21:20:58 -0500 Date: Thu, 6 Mar 2008 18:20:40 -0800 (PST) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Nick Piggin cc: Pekka Enberg , netdev@vger.kernel.org, Linux Kernel Mailing List , yanmin_zhang@linux.intel.com, David Miller , Eric Dumazet Subject: Re: [rfc][patch 1/3] slub: fix small HWCACHE_ALIGN alignment In-Reply-To: <20080307020443.GA21185@wotan.suse.de> Message-ID: References: <20080303201701.GF8974@wotan.suse.de> <84144f020803031330i2c0ea1f6kc5b02c8b26145797@mail.gmail.com> <47CC6F30.50802@cs.helsinki.fi> <20080305002821.GD1510@wotan.suse.de> <20080306024904.GA27150@wotan.suse.de> <20080307020443.GA21185@wotan.suse.de> 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: 941 Lines: 26 On Fri, 7 Mar 2008, Nick Piggin wrote: > > Do you have a case in mind where that would be useful? We had a > > Patch 3/3 Those already have SLAB_HWCACHE_ALIGN. The point is to switch off alignment for UP? Cant we do that with SLAB_HWCACHE_ALIGN too since SLOB seemed to work successfully without it in the past? > > Note that there is also KMEM_CACHE which picks up the alignment from > > the compiler. > > Yeah, that's not quite as good either. My allocation flag is dynamic, so > it will not bloat things for no reason on UP machines and SMP kernels. > It also aligns to the detected machine cacheline size rather than a > compile time constant. Is that really a noteworthy effect? -- 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/