[solved] Multiple realtime audio CPU's not used?


It looks like the multiple realtime audio CPU’s that I configure in settings are not actually used for vsti’s.

I have downloaded the demo version of Serum vst and this is seriously CPU heavy especially when using multiple notes. A common way I use to deal with this in Ableton Live is to just split the keyboard in multiple sections and assign the same vst with the same preset to the different sections. Then I assume Ableton splits those vst’s over multiple cpu threads, because the CPU usage stays within 60% (which is around normal for the preset I use). Even if I play a lot of notes at the same time.

However when I apply the same trick in Renoise (assign Serum twice to different instrument slots, then ‘split’ the midi keyboard to both of them). The CPU is still going up to 99% as if all vst’s are still using the same CPU.

When I use one instance of Serum and play the same chord progression in both Renoise and Live, both hit 99% CPU and start stuttering.

When I use the same preset and the same splitpoint of the keyboard and I play the same chord progression on two instances in both Renoise and Live, Renoise hits 99% and starts stuttering while Live stays around 60% and the sound is fine.

Not sure if it is designed this way of if it’s a bug. It is probably a lot of work to rewire the internals to make use of the multiple CPU’s like this, but if Renoise want’s to be able to compete with Live in this regard, this should definitely be fixed imho.

I use Windows 7, 64bit, Renoise 64bit + Serum 32bit, Live 32bit + Serum 32bit.

CPU is i7 quadcore with 8 threads.

Hopefully this can be addressed as it would make Renoise much more powerfull.

Or maybe I’m just doing something wrong… if so, please point that out to me.

Kind regards,

Ah. This seems to be indeed my own mistake.

I routed them both to one track. When routing to different tracks, the CPU usage is perfectly fine.

Sorry for disturbing. This can be closed. :blush: