From: Thomas Gleixner <tglx@linutronix.de>
To: Ingo Molnar <mingo@elte.hu>
Cc: Florian Schmidt <mista.tapas@gmx.net>,
Lee Revell <rlrevell@joe-job.com>,
Paul Davis <paul@linuxaudiosystems.com>,
LKML <linux-kernel@vger.kernel.org>,
mark_h_johnson@raytheon.com, Bill Huey <bhuey@lnxw.com>,
Adam Heath <doogie@debian.org>,
Michal Schmidt <xschmi00@stud.feec.vutbr.cz>,
Fernando Pablo Lopez-Lezcano <nando@ccrma.stanford.edu>,
Karsten Wiese <annabellesgarden@yahoo.de>,
jackit-devel <jackit-devel@lists.sourceforge.net>,
Rui Nuno Capela <rncbc@rncbc.org>, "K.R. Foley" <kr@cybsft.com>
Subject: Re: [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4]
Date: Mon, 01 Nov 2004 16:47:20 +0100 [thread overview]
Message-ID: <1099324040.3337.32.camel@thomas> (raw)
In-Reply-To: <20041101140630.GA20448@elte.hu>
On Mon, 2004-11-01 at 15:06 +0100, Ingo Molnar wrote:
> 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:
Yes, I was running hackbench as usual
> http://redhat.com/~mingo/realtime-preempt/
>
> Thomas, can you confirm that this kernel fixes the irqs-off latencies?
> (the priority loop indeed was done with irqs turned off.)
The latencies are still there. I have the feeling it's worse than 0.6.2.
It's definitely irq-off. I have a card with a controller, which produces
an 2ms interrupt. The controller busy loops until the second level ack
is done. The time is measured from raising the irq to the 2nd level ack.
The irqhandler is using NODELAY and keeps irqs disabled. So the measured
time in the controller is the irqs disabled time + the irq latency
(which is ~7µs). The testrun on 0.6.5 showed latencies up to 600µs
within 10 minutes.
After 15 Mintes the keyboard was dead.
I'm porting some of the Libertos debugging stuff into 0.6.5, so I can
instrument the problem.
More later.
tglx
next prev parent reply other threads:[~2004-11-01 16:03 UTC|newest]
Thread overview: 152+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1099008264.4199.4.camel@krustophenia.net>
2004-10-29 0:57 ` [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4] Paul Davis
2004-10-29 2:10 ` Lee Revell
2004-10-29 8:02 ` Ingo Molnar
2004-10-29 8:21 ` Thomas Gleixner
2004-10-29 9:09 ` Ingo Molnar
2004-10-29 11:01 ` Paul Davis
2004-10-29 11:14 ` Ingo Molnar
2004-10-29 11:26 ` Paul Davis
2004-10-29 11:36 ` Ingo Molnar
2004-10-29 13:35 ` Paul Davis
2004-10-29 13:55 ` Ingo Molnar
2004-10-29 14:03 ` Paul Davis
2004-10-29 14:15 ` Ingo Molnar
2004-10-29 16:14 ` Ingo Molnar
2004-10-29 16:21 ` Ingo Molnar
2004-10-29 16:32 ` Florian Schmidt
2004-10-29 16:23 ` Ingo Molnar
2004-10-29 16:31 ` Ingo Molnar
2004-10-29 16:37 ` Ingo Molnar
2004-10-29 16:53 ` Ingo Molnar
2004-10-29 17:16 ` Florian Schmidt
2004-10-29 17:02 ` Ingo Molnar
2004-10-29 17:09 ` Ingo Molnar
2004-10-29 17:16 ` Ingo Molnar
2004-10-29 17:33 ` Florian Schmidt
2004-10-29 17:21 ` Ingo Molnar
2004-10-29 17:22 ` Ingo Molnar
2004-10-29 18:36 ` Florian Schmidt
2004-10-29 20:33 ` Ingo Molnar
2004-10-29 20:51 ` Paul Davis
2004-10-29 21:11 ` Ingo Molnar
2004-10-30 1:06 ` Paul Davis
2004-10-30 11:34 ` Ingo Molnar
2004-11-26 17:16 ` [Jackit-devel] " Jack O'Quin
2004-10-29 20:42 ` Ingo Molnar
2004-10-29 21:31 ` Florian Schmidt
2004-10-29 21:25 ` Ingo Molnar
2004-10-29 21:42 ` Lee Revell
2004-10-29 21:46 ` Ingo Molnar
2004-10-29 21:53 ` Lee Revell
2004-10-29 23:12 ` Lee Revell
2004-10-30 11:58 ` Ingo Molnar
2004-10-30 17:49 ` Lee Revell
2004-10-30 19:17 ` Ingo Molnar
2004-10-30 19:43 ` Lee Revell
2004-10-30 19:47 ` Florian Schmidt
2004-10-30 19:37 ` Ingo Molnar
2004-10-30 19:57 ` Florian Schmidt
2004-10-30 19:52 ` Lee Revell
2004-10-30 20:15 ` Florian Schmidt
2004-10-30 20:26 ` Lee Revell
2004-10-30 21:13 ` Florian Schmidt
2004-10-30 21:26 ` Lee Revell
2004-10-30 21:38 ` Florian Schmidt
2004-10-30 23:12 ` Lee Revell
2004-10-31 12:07 ` Ingo Molnar
2004-10-31 12:48 ` Ingo Molnar
2004-10-31 12:54 ` Lee Revell
2004-10-31 13:13 ` Ingo Molnar
2004-10-31 13:40 ` Ingo Molnar
2004-10-31 15:20 ` Florian Schmidt
2004-10-31 15:59 ` Florian Schmidt
2004-10-31 19:06 ` Florian Schmidt
2004-11-01 13:42 ` Ingo Molnar
2004-11-01 13:53 ` Ingo Molnar
2004-11-01 14:06 ` Ingo Molnar
2004-11-01 15:47 ` Thomas Gleixner [this message]
2004-11-01 17:55 ` Lee Revell
2004-11-01 17:58 ` Thomas Gleixner
2004-11-01 18:43 ` Ingo Molnar
2004-11-01 18:46 ` Ingo Molnar
2004-11-01 22:30 ` Florian Schmidt
2004-11-01 22:40 ` Bill Huey
2004-11-01 22:51 ` Florian Schmidt
2004-11-01 22:59 ` Bill Huey
2004-11-02 8:02 ` Ingo Molnar
2004-11-02 8:07 ` Ingo Molnar
2004-11-02 15:06 ` [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.6.8 Ingo Molnar
2004-11-02 17:52 ` K.R. Foley
2004-11-02 19:37 ` Ingo Molnar
2004-11-02 19:40 ` K.R. Foley
2004-11-02 19:24 ` Norberto Bensa
2004-11-02 19:35 ` Ingo Molnar
2004-11-02 23:09 ` Karsten Wiese
2004-11-03 1:12 ` Ingo Molnar
2004-11-03 10:15 ` Karsten Wiese
2004-11-01 17:04 ` [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4] Rui Nuno Capela
2004-11-01 17:08 ` Thomas Gleixner
2004-11-01 20:00 ` Rui Nuno Capela
2004-11-01 17:24 ` K.R. Foley
2004-11-02 0:22 ` Michal Schmidt
2004-11-01 13:54 ` Paul Davis
2004-11-01 14:30 ` Ingo Molnar
2004-11-01 19:30 ` Paul Davis
2004-11-02 8:17 ` Ingo Molnar
2004-11-01 14:03 ` Florian Schmidt
2004-11-01 14:12 ` Ingo Molnar
2004-11-01 15:29 ` K.R. Foley
2004-11-02 23:41 ` [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.6] Remi Colinet
2004-11-03 1:04 ` Remi Colinet
2004-11-01 11:55 ` [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4] Ingo Molnar
2004-11-01 12:37 ` Ingo Molnar
2004-11-01 12:35 ` Thomas Gleixner
2004-11-01 12:51 ` Ingo Molnar
2004-11-01 13:15 ` Ingo Molnar
2004-11-01 13:40 ` Florian Schmidt
2004-11-01 13:48 ` Ingo Molnar
2004-11-01 16:47 ` Rui Nuno Capela
2004-10-31 23:16 ` Michal Schmidt
2004-11-01 0:05 ` Magnus Määttä
2004-10-31 13:11 ` Ingo Molnar
2004-10-31 14:11 ` Florian Schmidt
2004-10-31 13:22 ` Ingo Molnar
2004-10-31 14:28 ` Florian Schmidt
2004-10-31 13:30 ` Ingo Molnar
2004-10-31 21:58 ` Rui Nuno Capela
2004-10-31 22:11 ` K.R. Foley
2004-10-31 2:20 ` Lee Revell
2004-10-31 10:00 ` Florian Schmidt
2004-10-31 12:09 ` Lee Revell
2004-10-31 12:19 ` Ingo Molnar
2004-10-31 12:35 ` Lee Revell
2004-10-31 12:39 ` Ingo Molnar
2004-10-30 20:05 ` Lee Revell
2004-10-30 20:29 ` Florian Schmidt
2004-10-30 0:15 ` Lee Revell
2004-10-29 22:31 ` Florian Schmidt
2004-10-29 22:50 ` Florian Schmidt
2004-10-30 13:15 ` Ingo Molnar
2004-10-30 17:53 ` Florian Schmidt
2004-10-30 3:36 ` Lee Revell
2004-10-30 3:48 ` Lee Revell
2004-10-30 11:16 ` Ingo Molnar
2004-10-30 17:44 ` Lee Revell
2004-10-30 11:28 ` Ingo Molnar
2004-10-30 11:33 ` Ingo Molnar
2004-10-30 13:16 ` Florian Schmidt
2004-10-30 1:10 ` Lee Revell
2004-10-30 1:15 ` Lee Revell
2004-10-29 8:59 ` Ingo Molnar
2004-10-29 9:29 ` Ingo Molnar
2004-10-29 13:48 ` Ingo Molnar
2004-10-29 14:19 ` Paul Davis
2004-10-29 14:27 ` Ingo Molnar
2004-10-29 14:31 ` Ingo Molnar
2004-10-29 14:38 ` Paul Davis
2004-10-29 19:33 ` Lee Revell
2004-10-29 19:35 ` Thomas Gleixner
2004-11-01 14:32 Mark_H_Johnson
2004-11-01 14:36 ` Ingo Molnar
-- strict thread matches above, loose matches on Subject: below --
2004-11-01 16:34 Mark_H_Johnson
2004-11-01 18:48 ` Ingo Molnar
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