[arch-proaudio] Changes to jack/jack2 and realtime privileges

[Joakim Hernberg]

On Wed, 22 Aug 2018 12:23:37 +0200
Ralf Mardorf <ralf.mardorf at alice-dsl.net> wrote:

> On Tue, 21 Aug 2018 23:43:26 +0200, David Runge wrote:
> >It is now an optional dependency to jack and jack2{,-dbus} and can of
> >course also be dependend upon from other packages if needed.  

> What's the advantage of 'rtprio 98' over upstream's recommendation
> 'rtprio 99'?

That's very simple.  At 99 there are some kernel management threads
running, like the watchdogs, the ones responsible to move tasks from one
CPU to another, etc.  Best not to interfere with that.

> The packages URL is even more confusing.

Yes the wiki pages are going to need a serious haircut at some point.

> What are the below rules good for?

> 40-realtime-privileges.rules
># rw access to /dev/cpu_dma_latency to prevent CPUs from going into
>idle state

This one is quite clear, no?  Not available on all CPUs

># rw access to /dev/rtc0
># rw access to /dev/hpet0

AFAIK, these are useless on a modern kernel like ours.  I would like to
see them removed..

-- 

   Joakim