Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932148AbWAEUXQ (ORCPT ); Thu, 5 Jan 2006 15:23:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932153AbWAEUXQ (ORCPT ); Thu, 5 Jan 2006 15:23:16 -0500 Received: from smtp.osdl.org ([65.172.181.4]:37290 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S932148AbWAEUXP (ORCPT ); Thu, 5 Jan 2006 15:23:15 -0500 Date: Thu, 5 Jan 2006 12:15:25 -0800 (PST) From: Linus Torvalds To: Martin Bligh cc: Matt Mackall , Arjan van de Ven , Chuck Ebbert <76306.1226@compuserve.com>, Adrian Bunk , Andrew Morton , Ingo Molnar , linux-kernel , Dave Jones , Tim Schmielau Subject: Re: [patch 00/2] improve .text size on gcc 4.0 and newer compilers In-Reply-To: Message-ID: References: <200601041959_MC3-1-B550-5EE2@compuserve.com> <43BC716A.5080204@mbligh.org> <1136463553.2920.22.camel@laptopd505.fenrus.org> <20060105170255.GK3356@waste.org> <43BD5E6F.1040000@mbligh.org> <43BD784F.4040804@mbligh.org> 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: 787 Lines: 21 On Thu, 5 Jan 2006, Linus Torvalds wrote: > > The cache effects are likely the biggest ones, and no, I don't know how > much denser it will be in the cache. Especially with a 64-byte one.. > (although 128 bytes is fairly common too). Oh, but validatign things like "likely()" and "unlikely()" branch hints might be a noticeably bigger issue. In user space, placement on the macro level is probably a bigger deal, but in the kernel we probably care mostly about just single cachelines and about branch prediction/placement. 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/