Re: nohz and strange sleep latencies

[Pavel Machek]

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
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/