Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 5 Mar 2001 13:45:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 5 Mar 2001 13:45:42 -0500 Received: from gateway.sequent.com ([192.148.1.10]:54810 "EHLO gateway.sequent.com") by vger.kernel.org with ESMTP id ; Mon, 5 Mar 2001 13:45:32 -0500 Date: Mon, 5 Mar 2001 10:41:18 -0800 From: Jonathan Lahr To: Manfred Spraul Cc: Jonathan Lahr , linux-kernel@vger.kernel.org Subject: Re: kernel lock contention and scalability Message-ID: <20010305104118.C6212@w-lahr.des.sequent.com> In-Reply-To: <20010215104656.A6856@w-lahr.des.sequent.com> <3A98D5D3.6A6B6686@colorfullife.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2i In-Reply-To: <3A98D5D3.6A6B6686@colorfullife.com>; from manfred@colorfullife.com on Sun, Feb 25, 2001 at 10:52:19AM +0100 X-Operating-System: Linux 2.0.32 on an i486 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Manfred Spraul [manfred@colorfullife.com] wrote: > > > lock contention work would be appreciated. I'm aware of timer scalability > > work ongoing at people.redhat.com/mingo/scalable-timers, but is anyone > > working on reducing sem_ids contention? > > Is that really a problem? > The contention is high, but the actual lost time is quite small. I agree it isn't a major performance problem under that workload. But, I thought since the contention was high that other workloads which may utilize it more might have shown it to be a significant problem. > I've attached 2 changes that might reduce the contention, but it's just > an idea, completely untested. Thanks for the insight into the sempahore subsystem and the suggested fixes. -- Jonathan Lahr IBM Linux Technology Center Beaverton, Oregon lahr@us.ibm.com 503-578-3385 - 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/