[linux-audio-user] midi timings

[James Stone]

On Sat, Jan 27, 2007 at 10:00:13AM +1100, we are wrote:
> hey crew.
> 
> just a quick question, i have had a lot of pain figuring out this midi
> timing issue but got it thanks to this page
> http://tapas.affenbande.org/wordpress/?page_id=40
> 
> when i
> cat /proc/sys/dev/rtc/max-user-freq
> 
> it returns
> 64
> 
> which is always useless for midi audio work. so as suggested i simply
> echo 8192 > /proc/sys/dev/rtc/max-user-freq
> 
> which brings it back up 8192.
> 
> so, how do i make this a permanent thing so i don't have to type it in
> at every startup.

You can just add the line

dev.rtc.max-user-freq=8192

to /etc/sysctl.conf

> also,
> 
> is this the best/standard way to fix my midi timing issue, it works
> but is there any diadvantage to it. i only wonder this because it
> defualts to 64.

I think the higher frequency puts more load on the system, though
64 sounds very low. The default is usually 250. IIRC this was
chosen by Linus et al. in order to not drain laptop batteries too
quickly... It is possible to set it to 1000Hz if you compile the
kernel yourself, but to get it to 8192 (if that is even
possible), the max-user-freq must be used.

As an aside: does anyone know if it makes any difference if it is
1000Hz or 8000Hz?

James