Help me understand Cubase AISO peaks

I need help understanding how to best utilize System resources while running Cubase. I’ve run a few tests with some interesting results.

Test 1: Load a single omnisphere multi (where its playing 8 patches at once + all its FX etc in stack Mode) and at a buffer size of 256, Multi processing on & AISO Guard on high. Result: AISO peaks. Whats weird is my CPU meter in activity monitor shows all CPU cores with tons of headroom & cubase using only 200% CPU (max is 100% x 24 for my cores + hyperthreading), but Cubase’s Real-time peak meter is maxing out. I’m guess this has something to do with a single instrument being loaded on a single CPU, and once you max out that CPU you are done - but I dont get why I dont see a single core maxing out in activity monitor? Notice that 88% of my CPU is idle!!


Test 2: Spread out this same Omninsphere multi across 8 different omnispheres each playing one patch. Buffer still at 256, Multi processing on & AISO Guard on high. Result: AISO is no where near peaking, even though according to Activity monitor the same CPU is being use. (see picture 2)

Does this mean that Cubase only uses multiple processing if you are playing multiple instruments? Does this mean it is best in general to treat multi-channel instruments like Omnisphere, Kontakt, Halion, etc as individual instruments and load more instances with single patches vs less instances full of patches? That seems to be the conclusion I’ve hit with my tests, but would love to hear from other users.

The ASIO monitors shows if the audio signal reaches the soundcard in time, so if it’s peaking it means that some audio chunks are not received in time, so the sound was interrupted. (audible or not)
If one of the cores is at it’s max, then it is indeed plausible to have a ASIO peak in the very near future, because the core has trouble keeping up with the rest.

On the other hand, the things you are noticing are also correct i presume, but not as such directly related to ASIO peaks.
Yes, the more you spread your instruments over multiple dll’s, the more options cubase has when doing the core handling. Most of the time this results in a far better general load overall (CPU).
When stacking is being done within a certain single vst, the entire package is handed over to cubase as one instrument. This can result in a heavier load on a single core or the cores that are reserved for processing that instrument.

As far as i understand, the internal settings of core handling within a vsti are not affecting the audio handling when running cubase. These settings are for standalone use (when the vsti has to do the core handling by itself).

But on the other hand, none of your cores are at max, so the peak is probably not related to the processer in this case.
When looking at the attachments you can clearly see that your video drivers are hanging. (on both pictures)
Imho the video driver (and the priority level it is giving) is interfering with your audio signal. If it has more priority at a certain moment then the audio signal, your chunks are waiting to be processed in a cue and what follows is that they are not processed in time, and the ASIO peak is nothing more then an indication of what has happened. Your audio chuncks arrived too late.

That this is not resulting in a peak when you have spread everything out over multiple ddl’s is indeed a logical indication that this is indeed a more efficient way of processing, so every chunk still gets in time on it’s arrival point. It’s probably a very powerfull computer.
But that video driver is something you should be looking in to, since imho that is what is causing the underperformance.

Hope this helps a bit, but it is just an opinion on a forum.
kind regards,
R.

But on the other hand, none of your cores are at max, so the peak is probably not related to the processer in this case.
When looking at the attachments you can clearly see that your video drivers are hanging. (on both pictures)
Imho the video driver (and the priority level it is giving) is interfering with your audio signal.

Those are more specifically the Cubase video engine files.
Best bet if not running any video in Cubase is to rename or move these items out of the components folder.
I doubt that these hanging will have any effect on your audio tbh.