Re: Responsiveness of 2.6.0-Test9

[Erwin Telser]

> Erwin Telser wrote:
> >Are there things to observe when switching from 2.4 to 2.6, if I want the
> > same responsiveness? I'm asking because I' ve made the following
> > observation. (I always had the feeling, 2.4 seems to faster, but this is
> > the first time it' s very obvious)
> >
> >I' ve connected two monitors on a Matrox G550. One runs with DRI the other
> > one doesn't (not possible with the current driver). The Monitor with DRI
> > I'm using as a TV Set, watching movies with xawtv. (With a bttv 878 tuner
> > card).
> >
> >Now with the 2.4.22 kernel (preemptible patch aplied) I can play the
> > little game kbounce on the other monitor, without to notice any slowdown,
> > no matter, whether xawtv is running or not.
> >
> >But with the 2.6 Kernel (compiled with preemptible option) the bouncing
> > balls slow down considerably, as soon as I move the mouse.
> >
> >I know the whole thing is a little foolish. But anyway, are there some
> > tricks to get the same responsiveness?
>
> Hi,
> Your report is not foolish at all ;)
> Please make sure your X process is at default static priority, 0.
> Report back if you are still having problems. What sort of processor
> do you have? Is your 2.6 video driver running with the same sort of
> acceleration as your 2.4 one (do you get the same frame rate in glxgears)?

I installed X from scratch and didn't edit any start script. so I assume, that 
it runs with priority 0. The processor is an Intel P4 2000MHz in an ASUS 
P4B266 Board. If I compare the frames per second with glxgears there is a 
slight advantage for 2.4

2.4: 
with DRI 358 - 364
without DRI 181 - 198

2.6
with DRI 350 - 362
without DRI 180 - 187

An even better way to show the differenze between 2.4 and 2.6 is to change the 
size of the xawtv window. If I do that, the slowdown is quite significant. 
But it happens only with xawtv. If I do the same with konqueror or MPlayer, 
nothing happens. A very strange thing are the values I get from ksysguard

Kernel 2.4, glxgears
user load: 3% - 4%
system load: 95%
IRQ per second: ~100

Kernel 2.6, glxgears
user load: 15%
system load: 85%
IRQ per second: ~1100 

Kernel 2.4, xawtv
user load: 2%
system load: 0%
IRQ per second: ~100

Kernel 2.6, xawtv
user load: 9%
system load: 0%
IRQ per second: ~1060 

Kernel 2.4, MPlayer
user load: 35%
system load: 2%
IRQ per second: ~1170

Kernel 2.6, MPlayer
user load: 42%
system load: 2%
IRQ per second: ~2130

Something is causing a high IRQ load with kernel 2.6. Probably an APIC 
problem?

Erwin

-
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/