From: Pavel Machek <pavel@ucw.cz>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>, kernel list <linux-kernel@vger.kernel.org>
Subject: Re: nohz and strange sleep latencies
Date: Sat, 24 Nov 2007 23:29:41 +0100 [thread overview]
Message-ID: <20071124222941.GA1544@elf.ucw.cz> (raw)
In-Reply-To: <alpine.LFD.0.9999.0711222121500.25057@localhost.localdomain>
On Thu 2007-11-22 21:29:51, Thomas Gleixner wrote:
> On Thu, 22 Nov 2007, Pavel Machek wrote:
> > > but perhaps somehow we miss this fact and fail to turn off the lapic
> > > clockevents drivers?
> >
> > Ok, I guess I'm lost. If I offline second CPU, I immediately get
> > 1000Hz timer tick... is that expected?
>
> Hmm. No. I have no idea why this is happening.
>
> 34196 total events, 55.083 events/sec
> echo 0 >/sys/devices/system/cpu/cpu1/online
> 36073 total events, 54.679 events/sec
Strange...
> Just to make sure what we are hunting: Do you have the same problem
> with an non-pavel-tainted 2.6.24-rc3 ?
The effect described above disappeared from both clean and
tainted-pavel trees...?
But I have verified again that time sleep 0.01 is perfectly willing to
sleep for 0.9second on untainted 2.6.24-rc3...
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
next prev parent reply other threads:[~2007-11-24 22:29 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-19 20:31 nohz and strange sleep latencies Pavel Machek
2007-11-19 20:55 ` Ingo Molnar
2007-11-19 21:11 ` Pavel Machek
2007-11-20 8:57 ` Ingo Molnar
2007-11-20 9:05 ` Ingo Molnar
2007-11-20 10:54 ` Pavel Machek
2007-11-20 20:54 ` Ingo Molnar
2007-11-20 22:48 ` Thomas Gleixner
2007-11-20 22:52 ` Ingo Molnar
2007-11-22 10:09 ` Pavel Machek
2007-11-22 18:51 ` Pavel Machek
2007-11-22 18:52 ` Pavel Machek
2007-11-22 20:29 ` Thomas Gleixner
2007-11-23 12:22 ` Pavel Machek
2007-11-24 22:29 ` Pavel Machek [this message]
2007-11-24 22:40 ` Pavel Machek
2007-11-24 23:29 ` Rafael J. Wysocki
2007-11-24 23:35 ` Rafael J. Wysocki
2007-11-25 21:51 ` Thomas Gleixner
2007-11-25 20:25 ` [patch] " Pavel Machek
2007-11-25 21:42 ` Thomas Gleixner
2007-11-26 11:54 ` Pavel Machek
2007-11-20 9:44 ` Thomas Gleixner
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