Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755761Ab0BOPcV (ORCPT ); Mon, 15 Feb 2010 10:32:21 -0500 Received: from lon1-post-1.mail.demon.net ([195.173.77.148]:43968 "EHLO lon1-post-1.mail.demon.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755588Ab0BOPcU (ORCPT ); Mon, 15 Feb 2010 10:32:20 -0500 Subject: Re: [PATCH] cfq: reorder cfq_queue removing padding on 64bit & allowing more objects/slab in it's kmem_cache From: Richard Kennedy To: Vivek Goyal Cc: Jens Axboe , Corrado Zoccolo , Jeff Moyer , Gui Jianfeng , lkml In-Reply-To: <20100215141626.GB5355@redhat.com> References: <1266243036.2149.21.camel@localhost> <20100215141626.GB5355@redhat.com> Content-Type: text/plain; charset="UTF-8" Date: Mon, 15 Feb 2010 15:32:18 +0000 Message-ID: <1266247938.7362.0.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.28.2 (2.28.2-1.fc12) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1323 Lines: 38 On Mon, 2010-02-15 at 09:16 -0500, Vivek Goyal wrote: > On Mon, Feb 15, 2010 at 02:10:36PM +0000, Richard Kennedy wrote: > > This removes 8 bytes of padding from struct cfq_queue on 64 bit builds, > > shrinking it's size to 256 bytes, so fitting into 1 fewer cachelines and > > allowing 1 more object/slab in it's kmem_cache. > > > > > > Signed-off-by: Richard Kennedy > > ---- > > patch against 2.6.33-rc8 > > tested on x86_64 AMDX2 > > > > regards > > Richard > > > > > > diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c > > index 023f4e6..db4c127 100644 > > --- a/block/cfq-iosched.c > > +++ b/block/cfq-iosched.c > > @@ -116,10 +116,10 @@ struct cfq_queue { > > unsigned long dispatch_start; > > unsigned int allocated_slice; > > /* time when first request from queue completed and slice started. */ > > + unsigned int slice_dispatch; > > Can you move it above the comment. The comment describes "slice_start" and > now comment and variable have been separated. > > Vivek Sure, no problem. I'll send out a new version. Richard -- 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/