Kernel-rt issues solved, but configuring X still is a PITA

[Ralf]

On Mon, 2010-12-27 at 23:56 +0100, Gerhard Lang wrote:
> Hi Ralf,
> nvidia prop drivers for your card never will  build with new 
> rt-kernels.  I see you compile customized kernels. I'd recommend trying 
> 2.3.36.xxx and even 2.6.37-rcxx with preempt settings. They run here on 
> a geriatric amd64x2 machine under lucid (10.04) ubuntustudio/kx mashing  
> with proprietary nvidia drivers, full rt support. Only missing against 
> rt-kernels is the possibility to adjust rtirq settings which as I see 
> *possibly* *might*  give *a* *little* benefit *only* for ffado/firewire 
> devices. Nevertheless I hope someone will implemet this rtirq tweaking 
> stuff into mainline kernels.
> Regards Gerhard

Hi Gerhard :)

kernel 2.6.31.6-rt19 + the proprietary nvidia driver is ok for my Suse
11.2 install and my GeForce 7200 GS (GeForce 7300 SE). I could test this
kernel-rt, if needed.
I don't categorically need the proprietary driver for Ubuntu Studio too,
but I wish to have the monitor's resolution settings for any WM and the
GDM login menu, a problem that should be independent from the used
driver.

I'm wary of non-kernels-rt, because I fear worsening MIDI jitter for PCI
MIDI. I get best results for my 2 Envy24 PCI MIDI devices and even for
my USB MIDI device, when running alsa-midi-latency-test, but I'm used to
hard real-time by the C64 and Atari ST + SMPTE sync to analog tape and
not fine with so called 'less' MIDI jitter by Linux. When using HPET
(HRTIMER) it might be, that it could be able to fix this, but only if I
can keep the audio latency as short as possible, because there is a
correlation between audio recordings of external MIDI equipment and MIDI
jitter.

I never compared just PREEMPT and PREEMPT RT.

At http://www.rncbc.org/jack/ Rui's version of rtirq still is
rtirq-20090920.tar.gz , should be equal to 20090920-0ubuntu1. I never
noticed any different between rtirq installed and customized and not
being installed or not being customized.

Thank you, I had issues regarding to the graphics with kernels-rt ex
2.6.31.6-rt19, but can't remember of what kind exactly.

Cheers!

Ralf