From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262377AbUJ0KnK (ORCPT ); Wed, 27 Oct 2004 06:43:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262367AbUJ0KnK (ORCPT ); Wed, 27 Oct 2004 06:43:10 -0400 Received: from imap.gmx.net ([213.165.64.20]:30608 "HELO mail.gmx.net") by vger.kernel.org with SMTP id S262377AbUJ0KlL (ORCPT ); Wed, 27 Oct 2004 06:41:11 -0400 X-Authenticated: #4399952 Date: Wed, 27 Oct 2004 12:58:09 +0200 From: Florian Schmidt To: Ingo Molnar Cc: "K.R. Foley" , linux-kernel@vger.kernel.org, Lee Revell , Rui Nuno Capela , Mark_H_Johnson@Raytheon.com, Bill Huey , Adam Heath , Thomas Gleixner , Michal Schmidt , Fernando Pablo Lopez-Lezcano , Alexander Batyrshin Subject: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0 Message-ID: <20041027125809.725900f6@mango.fruits.de> In-Reply-To: <20041027102921.GA28764@elte.hu> References: <417D4B5E.4010509@cybsft.com> <20041025203807.GB27865@elte.hu> <417E2CB7.4090608@cybsft.com> <20041027002455.GC31852@elte.hu> <417F16BB.3030300@cybsft.com> <20041027082831.GA15192@elte.hu> <20041027084401.GA15989@elte.hu> <20041027085221.GA16742@elte.hu> <20041027090620.GA17621@elte.hu> <20041027123329.14570992@mango.fruits.de> <20041027102921.GA28764@elte.hu> X-Mailer: Sylpheed-Claws 0.9.12b (GTK+ 1.2.10; i386-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 27 Oct 2004 12:29:21 +0200 Ingo Molnar wrote: > > pid 1286's current scheduling policy: SCHED_OTHER > > pid 1286's current scheduling priority: 0 > > ~$ chrt -p 1287 > > pid 1287's current scheduling policy: SCHED_OTHER > > pid 1287's current scheduling priority: 0 > > just curious, are these two important to the latency path of jackd, or > are they lowprio things and are thus at SCHED_OTHER intentionally? the latter. jackd has one RT thread for doing the grunt work and one which acts as a watchdog. The other two are SCHED_OTHER by design. > > Anyways i get xruns like crazy under load (like 200 in 10 minutes). It > > seems the scheduling class and high priority don't matter really as > > wiggling windows around on the screen or doing a "find /" can easily > > provoke xruns. > > yeah, i'm hunting a quite similar bug: i can see 'realfeel' latencies > generated by simple window scrolling. It is most likely a logic bug > somewhere - a missing reschedule check, irqs left disabled accidentally, > or something like that. Since some other workloads dont trigger it i > dont think i broke RT scheduling by itself - it is most likely some > non-core code somewhere missing a resched. Which doesnt make it less of > a problem, but it makes it harder to find :-| Hmm, you're right. It seems that diskload alone doesn't trigger the problem. it rather looks like graphics output/activity is the problem. Anyways i'm back in U3 w/o PREEMPT_REALTIME as V0.3.2 just hardlocked on me when i pressed ctrl-d in a root shell (in an xterm) to exit. Nothing has made it to the log. I haven't found out yet whether it's possible to use my old zx81 as serial console, so i can't help with OOPS/BUG output. flo