Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S271801AbUKAR34 (ORCPT ); Mon, 1 Nov 2004 12:29:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S272241AbUKAR34 (ORCPT ); Mon, 1 Nov 2004 12:29:56 -0500 Received: from mail3.utc.com ([192.249.46.192]:7313 "EHLO mail3.utc.com") by vger.kernel.org with ESMTP id S266857AbUKARYu (ORCPT ); Mon, 1 Nov 2004 12:24:50 -0500 Message-ID: <41867143.4020709@cybsft.com> Date: Mon, 01 Nov 2004 11:24:19 -0600 From: "K.R. Foley" Organization: Cybersoft Solutions, Inc. User-Agent: Mozilla Thunderbird 0.8 (X11/20040913) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Ingo Molnar CC: Florian Schmidt , Lee Revell , Paul Davis , Thomas Gleixner , LKML , mark_h_johnson@raytheon.com, Bill Huey , Adam Heath , Michal Schmidt , Fernando Pablo Lopez-Lezcano , Karsten Wiese , jackit-devel , Rui Nuno Capela Subject: Re: [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4] References: <20041031120721.GA19450@elte.hu> <20041031124828.GA22008@elte.hu> <1099227269.1459.45.camel@krustophenia.net> <20041031131318.GA23437@elte.hu> <20041031134016.GA24645@elte.hu> <20041031162059.1a3dd9eb@mango.fruits.de> <20041031165913.2d0ad21e@mango.fruits.de> <20041031200621.212ee044@mango.fruits.de> <20041101134235.GA18009@elte.hu> <20041101135358.GA19718@elte.hu> <20041101140630.GA20448@elte.hu> In-Reply-To: <20041101140630.GA20448@elte.hu> X-Enigmail-Version: 0.86.1.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1480 Lines: 40 Ingo Molnar wrote: > * Ingo Molnar wrote: > > >>>removing the poll() lines doesnt seem to impact the quality of the >>>data, but i still see roughly 50 usecs added to the 'real' latency >>>that i see in traces. >> >>this i think is related to what Thomas observed, that there's a new >>irqs-off critical section somewhere. (it's in the new priority >>handling code i think.) > > > ah, found it. Only RT tasks were supposed to get special priority > handling, while in fact all tasks got it - so when Thomas ran hackbench > (Thomas, you did, right?) it created an O(nr_hackbench) overhead within > the mutex code ... I've uploaded -V0.6.5 to the usual place: > > http://redhat.com/~mingo/realtime-preempt/ > V0.6.5 built and booted fine on my SMP workstation. However, just a few minutes after booting it exhibited behavior like a system does when you can't fork any new processses. The system was responsive. I could switch between windows. I could switch from X to a virtual terminal. I could type in commands but they never return. At the virtual terminal login I could type the login but never get a passwd prompt. Nothing in the logs during this timeframe. Reset button was the only way to recover. kr - 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/