Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965139AbWH2TKa (ORCPT ); Tue, 29 Aug 2006 15:10:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965261AbWH2TKa (ORCPT ); Tue, 29 Aug 2006 15:10:30 -0400 Received: from kanga.kvack.org ([66.96.29.28]:31979 "EHLO kanga.kvack.org") by vger.kernel.org with ESMTP id S965139AbWH2TK3 (ORCPT ); Tue, 29 Aug 2006 15:10:29 -0400 Date: Tue, 29 Aug 2006 15:10:15 -0400 From: Benjamin LaHaise To: Andi Kleen Cc: David Howells , Nick Piggin , Arjan van de Ven , Dong Feng , Paul Mackerras , Christoph Lameter , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Subject: Re: Why Semaphore Hardware-Dependent? Message-ID: <20060829191015.GL18092@kvack.org> References: <44F395DE.10804@yahoo.com.au> <1156750249.3034.155.camel@laptopd505.fenrus.org> <11861.1156845927@warthog.cambridge.redhat.com> <200608291256.54665.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200608291256.54665.ak@suse.de> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 683 Lines: 17 On Tue, Aug 29, 2006 at 12:56:54PM +0200, Andi Kleen wrote: > We've completely given up these kinds of micro optimization for spinlocks, > which are 1000x as critical as rwsems. And nobody was able to benchmark > a difference. That is false. It shows up on things like netperf on the P4, or the AF_UNIX component of lmbench. -ben -- "Time is of no importance, Mr. President, only life is important." Don't Email: . - 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/