Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759613AbXFUUMQ (ORCPT ); Thu, 21 Jun 2007 16:12:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755818AbXFUUMA (ORCPT ); Thu, 21 Jun 2007 16:12:00 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:58746 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755492AbXFUUL7 (ORCPT ); Thu, 21 Jun 2007 16:11:59 -0400 Date: Thu, 21 Jun 2007 13:10:03 -0700 (PDT) From: Linus Torvalds To: Ingo Molnar cc: Eric Dumazet , Chuck Ebbert , Jarek Poplawski , Miklos Szeredi , chris@atlee.ca, linux-kernel@vger.kernel.org, tglx@linutronix.de, akpm@linux-foundation.org Subject: Re: [BUG] long freezes on thinkpad t60 In-Reply-To: <20070621195659.GA22303@elte.hu> Message-ID: References: <20070620093612.GA1626@ff.dom.local> <20070621073031.GA683@elte.hu> <20070621160817.GA22897@elte.hu> <467AAB04.2070409@redhat.com> <20070621202917.a2bfbfc7.dada1@cosmosbay.com> <20070621195659.GA22303@elte.hu> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1029 Lines: 30 On Thu, 21 Jun 2007, Ingo Molnar wrote: > > I can understand why no data is saved by this change: gcc is aligning > the next field to a natural boundary anyway and we dont really have > arrays of spinlocks (fortunately). Actually, some data structures could well shrink. Look at "struct task_struct", for example. Right now it has two spinlocks right next to each other (alloc_lock and pi_lock). Other data structures may have things like bitfields etc. But yeah, I'd not expect that to be very common, and in some cases you might have to re-order data structures to take advantage of better packing, and even then it's probably not all that noticeable. > but this is certainly not something for 2.6.22, it's an early 2.6.23 > matter i suspect. Oh, absolutely. Linus - 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/