From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267278AbUHIV3o (ORCPT ); Mon, 9 Aug 2004 17:29:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267314AbUHIV27 (ORCPT ); Mon, 9 Aug 2004 17:28:59 -0400 Received: from dragnfire.mtl.istop.com ([66.11.160.179]:28352 "EHLO dsl.commfireservices.com") by vger.kernel.org with ESMTP id S267278AbUHIV12 (ORCPT ); Mon, 9 Aug 2004 17:27:28 -0400 Date: Mon, 9 Aug 2004 17:31:19 -0400 (EDT) From: Zwane Mwaikambo To: Andi Kleen Cc: linux-kernel@vger.kernel.org, akpm@osdl.org, mpm@selenic.com Subject: Re: [PATCH][2.6] Completely out of line spinlocks / x86_64 In-Reply-To: <20040809132308.7312656b.ak@suse.de> Message-ID: References: <20040809132308.7312656b.ak@suse.de> 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 On Mon, 9 Aug 2004, Andi Kleen wrote: > I think the 50k number is wrong. I took a look at it and the big > difference is only seen when you enable interrupts during spinning, which > we didn't do before. If you compare it to the old implementation the > difference is much less. Yes agreed the increase wouldn't be of as high a magnitude if compared to the original code, but it's still a decent saving. > I don't really like the config option. Either it's a good idea > then it should be done by default without option or it should not be done at all. > > Did you do any lock intensive benchmarks that could show a slowdown? I went for a file IO type benchmark, the differences looked like statistical noise, possibly the best bet would be to check for cache hits/misses. > You should make this file assembly only. Ok you're the second person to mention that, i don't have a problem with switching to assembly only and dumping the exports in x8664_ksyms.c Thanks, Zwane