Re: [Jack-Devel] The Situation(s) With JACK

On Thu, Dec 08, 2011 at 08:04:57AM -0500, Paul Davis wrote:
 
>                                     It Has To Stop.

What can I say ? For at least the last five years or so
Jack for me 'just works'. Honestly, I can't remember the
last time I had any problem with it. Maybe that is because
I stay away from obese desktops or anything that tries to
hide or automate system configuration. I may wish it had
some features that it hasn't, or the inverse, but that is
a different subject. It just works. 

And yes, a lot of effort is probably wasted in maintaining
epx(1) versions. 

I've no idea what direction your proposal will take.
One option would be to restart from scratch, to define
and implement a 'next generation' Jack that could be
quite different from the current one, and that could
replace it in say a year or so. In that case I do have
some ideas. But I suspect that is not your intention.

One good reason to have a fresh look at what Jack is
supposed to do is the fact that SMP systems are more
or less the norm today. And complex apps (A3 being
the prime example) are taking advantage of that and
organising their internal processing using multiple
threads. No doubt more will follow. Yet, scheduling
in Jack remains on a per-process basis. That means
that e.g. if app B depends on input from app A, the
entire B is made to wait until all of A has done its
work, while the actual dependencies may be much more
fine-grained. There are several ways to address this.
One would be to have a single 'audio engine' process
and delegate all audio processing to it. That would
of course mean that all security is lost, a single
rogue audio routine could bring down everything. 
Another solution would be to make Jack trigger port
or groups of ports instead of a process. So anything
in B that depends on A would run as soon as all output
from A that a part of B depends on is available. In
other words, the signal graphs becomes global. That
would also allow B to be a insert of A without adding
latency etc.

But I'm dreaming. 

Ciao,

-- 
FA

Vor uns liegt ein weites Tal, die Sonne scheint - ein Glitzerstrahl.

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