[LAD] ALSA MIDI latency test results are far away from reality

[Ralf Mardorf]

On Wed, 2010-07-14 at 21:45 +0200, Robin Gareus wrote:
> On 07/14/2010 03:23 PM, Ralf Mardorf wrote:
> 
> [..]
> > $ su -c "chgrp audio /dev/hpet"
> Its also writable for the group, right?
> 
> > $ su -c "sysctl -w dev.hpet.max-user-freq=64"
> 
> Documentation on this value is hard to come by, but I think it's unit is
> Hz. So you'll want

Yep :). I've got no idea what would be better a high or a low value, but
at least 64 when using HR timer was better than using the regular timer.
Unfortunately not many apps are able to run, when HR timer is used.
Usage of HR timer can freeze the system, e.g. Rosegarden does this on my
machine. I also need to start 'qtractor filename'. If I first start
Qtractor and than try to load a session, here are issues because HR
timer already is captured.

I guess one would be more flexible, if not using HR timer. I didn't
tested if there will be a difference when using the PCI MIDI. I'll do
this also ASAP. As I mentioned before, for USB MIDI there is a big
difference.

No thunder, no storm anymore, but there was a rainbow some minutes
ago :)

- Ralf

>   su -c "sysctl -w dev.hpet.max-user-freq=1024"
> or even more :)
> 
> try:
> echo 2048 | sudo tee /sys/class/rtc/rtc0/max_user_freq
> echo 2048 | sudo tee /proc/sys/dev/hpet/max-user-freq
> 
> [..]
> ciao,
> robin
> 
>