Re: [LAD] jack_midi in jackd and jackdmp

Am Freitag, den 03.04.2009, 20:37 +0200 schrieb hermann meyer:
> Am Freitag, den 03.04.2009, 12:49 -0500 schrieb Gabriel M. Beddingfield:
> > On Fri, April 3, 2009 10:38 am, hermann meyer wrote:
> > > I open 2 clients because I wont 2 treads and give one (the midi tread) a
> > > lower prio with pthread_setschedprio. I first try to open the treads
> > > from one client, but I cant figure out how to do, with 2 clients that
> > > work fine with jackd.
> > > I give the midi tread a lower prio, because at least it is a audio app,
> > > so midi is "just a gast". On low level CPU's this protect the DSP for
> > > xrun's when the CPU limit is reached.
> >
> > Have you run in to problems with a single-client scheme? Was it giving
> > you xruns? IMHO, this is premature optimization. Doing two clients and
> > synchronizing threads is hard, error-prone work -- why not let JACK do
> > that work for you?
>
> This is the way I learn,I experience it a lot. Running the midi part at a
> lower prio helps to save CPU time for audio tread's. The effekt only turn in
> when the CPU is overload, then the audio data flow run first. When everything
> is in normal range, it effect nothing, I meen -20 is higher then every app
> running without a rt acces. I only can figure out how to do that when I open 2 clients.
>
> > Besides, if your goal is to ignore MIDI input when the CPU load gets too
> > high, why not do something like:
> >
> > process(){
> > if( ! too_busy_for_midi() ) {
> > // process MIDI
> > }
> >
> > // process AUDIO
> > }
> >
> > BTW, I see that your midi_process() is reading from a ringbuffer -- who is
> > *writing* to it?
> >
> Yes, this is new, I have used jack_midi_event_reserve befor, running it
> in the compute_midi() part. I switch to the ringbuffer (thanks to Edward
> Tomasz Napierala) because I guess first it is this part witch broke my
> app.
>
> It's the DSP.compute_midi(nframes);
>
> you can found it here :
> http://apps.sourceforge.net/trac/guitarix/browser/trunk/src/dsp.cpp
>
> > > Isn't it common open 2 Clients ?
> >
> > I don't think so.
> >
>
> regards hermann
>
 I have commit the working code now , thanks to all for your help. :)

_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev@email-addr-hidden
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Received on Sat Apr 4 00:15:03 2009