Thanks Paul -
Does one install JACK (daemon, I remember of it but haven't encountered it in some time) used in lieu of Pulse Audio (that came with Ubuntu linux) or alongside Pulse Audio?
I expect to use ring buffers sufficient to prevent underruns, but I haven't investigated the length/depth of the buffers needed to accomplish that.
2 cents of jambo...
PulseAudio has a solely unique purpose of serving systemd panacea...
It is absolutely useless (as systemd is as well.. ) and against all real time applications ..
reason being is systemd doing ad hocs things (it should not) in the background
Both can/should be removed in full without loosing any type of functionality and with a great (much much great) improvement in security for a dedicated DIGITAL SIGNAL PROCESSING machine...
As systemd is deeply buried in the install embracing several dozens tools and compilation options.. it is mostly IMPOSSIBLE to be removed... but PulseAudio is a tiny useless applet that can be removed safely...
Reason being is that the very same EGOtrip author of systemd is also the author of PulseAudio and both serve nothing for real in a DSP machine... the PulseAudio just completes systemd...
A single safe SystemV init coupled with vanilla ALSA works 100 times fold better in any way...
JACK is a very optimized REAL TIME daemon which should be run with a considerable criteria setup.. done to integrate JACK alongside all the DSP pipes available via LADSPA...
It can handle several threads safely with a real time schedule almost flawless with proper setup
I have done an exercise some years ago trying to integrate my instrument widget set with SIGROK and JACK and I was deeply surprised how damn well the JACK signal processor can handle data I/O of any kind for INSTRUMENTATION as well...
wondering how high can raise frequency these days...
The setup requires in the very first place to ditch systemd because that thing is a REAL TIME PIG... it was not designed for real time applets or even DSP machines at all.. it serves other way different reasons.. the EGOtrip of the author...
Screenshot of my INSTRUMENTATION widgets integrated with JACK and SIGROK using a FULLY CAPABLE LADSPA Plugin console... it can be raised to almost 500kHz without changing a bit...
It took me about a week to write that thing... just a toy.. amazingly well how it works.
The applet was written in plain GTK tripple buffered (all instruments..) each instrument with a separate thread and each DSP with own thread as well...
It can interface ANYTYPE of JACK device available in the system..
SCOPE + DMM + FUNCTION GENERATOR... with LADSPA support..
Paul