Re: CFS not suitable for desktop computers

Mike Galbraith
2009-05-05T07:52:10Z

On Tue, 2009-05-05 at 07:42 +0200, Mike Galbraith wrote:
> On Mon, 2009-05-04 at 15:01 -0600, Chris Friesen wrote:
> > Nico Schümann wrote:
> > > Thank you Ray Lee and Mike Galbraith for your responses, I ran the
> > > script and attached its gathered information.
> > >
> > > Mike Galbraith wrote:
> > >> How hard is hard? Can you describe the loads you're having trouble
> > >> with, and the hardware you're running them on?
> > >>
> > >>
> > > I could reproduce "hard" load by just compiling the linux kernel, make
> > > -j3 while reading mails with Thunderbird, which is not that hard
> > > foreground load. Thunderbird starts reacting really slowly while compiling.
> >
> > I wonder if this could be related to I/O rather than the task scheduler
> > proper.
>
> That's something I was wondering as well, particularly when I noticed
> he's using data=journal and anticipatory io-scheduler.

Well, I offlined 3 of 4 cores, set data=journal, and throttled down to
1.6GHz to load test a bit, and it didn't make any difference with
_Evolution_ and a make -j3 running. Evolution remained responsive.

I can feel the load though. X here is unaccelerated (damn nvidia), so
despite heftier core (Q6600), CPU usage while browsing mail is pretty
similar to Nico's data, often heavier. Behavior I see here isn't bad at
all.. unless I move a window that is, X then becomes a major oinker, so
I feel every bit of load. That's unpleasant, but expected.

I have an old P4 lying about (has X candy). I'll update it and try some
UP testing. Can't test Thunderbird though.

-Mike