Re: 2.6.24-git4+ regression

From: Lukas Hejtmanek
Date: Mon Feb 04 2008 - 12:01:38 EST


On Mon, Feb 04, 2008 at 03:45:10PM +0100, Peter Zijlstra wrote:
> > see my previous mail to Ingo (you were Cc.), latency top says that Xorg and
> > gnome-terminal suffers 300+ms latency in scheduler: waiting for cpu.
>
> what happens when you turn CONFIG_FAIR_GROUP_SCHED off?

If I disable CONFIG_FAIR_GROUP_SCHED, it is a lot better. I would not call it
optimal, though.

Xorg has 20ms latency, gnome-terminal another 20ms latency. If I just press
a key (a letter for instance) to see how autorepeat fills terminal, one can
see that autorepeat is not smooth and it is stopping for a little while
(really extra short stops are visible but still visible). But it is really
a ton better that it was with fair group sched.

So, any conclusion? The case is closed or any further investigation should be
done?

--
Lukáš Hejtmánek
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