Re: strange keyboard lag after suspend testing

[Rafael J. Wysocki]

On Tuesday, 20 March 2007 17:38, Pavel Machek wrote:
> Hi!
> 
> > > >> > I was testing suspend in 2.6.21-rc4 a lot, and now... machine feels
> > > >> > like someone added 50..100msec delay somewhere in keyboard
> > > >> > handling. Mouse does not seem affected. /proc/interrupts seem to
> > > >> > increase as they should, for both keyboard and mouse. Can someone
> > > >> > reproduce it? Any ideas how to debug it?
> > > >>
> > > >> Probably just asking the obvious:
> > > >> it's not a trivial "failed to re-configure repeat rate upon resume"
> > > >> (which one could rule out by running "kbdrate" again)
> > > >> but a lag in some interrupt handler or somewhere else deeper, right?
> > > >
> > > >No, it is not keyboard rate. Keyboard lags during normal typing,
> > > >sometimes letters come in groups of two or so...
> > > 
> > > I might start looking at embedded controller changes and switches. If
> > > ACPI misbehaves that could starve keyboard controller... But you
> > > said
> > 
> > Mouse _seems_ okay, but I'm not sure if I'd notice lag there.
> > 
> > > that mouse is OK... Hmm, what happens if you load evbug and type while
> > > watching syslog. Do you observe the same delays?
> > 
> > Hmm, seems that it only happens in X... so maybe it is some strange
> > scheduling artefact?
> > 
> > Hmm, something is wrong here:
> > 
> > On console, I get expected 4-5 ticks a second. In x in gnome-terminal,
> > I get this:
> 
> It gets weirder: I killed some tasks and now: (on unloaded system
> running X, notice that top latency was ~1sec at 33:09).
> 
> root@amd:~# while true ; do echo -n . ; sleep .2; date; done
> .Tue Mar 20 17:33:07 CET 2007
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> .Tue Mar 20 17:33:10 CET 2007
> .Tue Mar 20 17:33:10 CET 2007
> .Tue Mar 20 17:33:10 CET 2007
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> .Tue Mar 20 17:33:11 CET 2007
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> 
> As soon as I load the cpu up with while1, machine starts to behave.
> 
> When I turn on bluetooth (USB), ACPI can no longer use C3, and machine
> starts to behave. Hmm?

Smells like a cpufreq problem or something related.

Greetings,
Rafael
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