I am creating a music software using jack, that has multiple outputs (16). When running full dsp process in my program (many synths, samplers, etc..), the cpu load is little high but nothing near troubling. This is when jack client's outputs are unconnected or connected straight to sound card outputs.
So, then as I start Ardour and open empty template (no plugins or anything), cpu load stays down in 5% (monitoring with top) until I connect my program's outputs into Ardour inputs. After that, Ardour cpu usage jumps to 80-95% and causes everything to slow down into unusable, even if my prog is not processing much anything. This doesn't make any sense as puredata instances with the same or higher amount of jack outputs are not causing similar cpu loads to ardour (empty or even full with plugins).
In my program, all outputs are processed in the same jack callback function, is this the correct way of doing it for multiout ? What could be causing this cpu peak ? I am using rt kernel on linux test machine and my program's gui is drawn with SDL.
It is starting to be very cool program, but this problem makes it kinda unusable.