Please take a look at TBProAudio's recent implementation of silence bypass.
Many analog modelling plugins don't output perfect silence and there's usually at least one of them in a complex signal path which vastly reduces the benefit of this feature. Valhalla Delay outputs very low level noise (as I'm sure many other tape delays do). The result is complex and resource intensive patches that would most benefit from bypassing processing when they aren't receiving input are the least likely to have it engaged.
Using 10% of the CPU to process noise flickering at -100dB makes as little sense as processing bit-perfect silence.
Being able to set a custom threshold of what's considered "silence" based on the input while idle/stopped would be a major improvement for optimizing CPU usage.
I am not sure such options would make sense here. Since these plug-in all have a built-in gate, maybe that's what you want to add after the plug-ins that might generate low level noise to make it an explicit choice.
It was a quick test with a 3rd party gate first but it's the same with the built-in one. Neither seemed to reduce CPU usage as expected so I just assumed using a gate within the plugin didn't disable further processing. I should've explained better. The issue isn't really 3rd party plugins in the Blue Cat hosts, but inaudible noise elsewhere in the signal path preventing the CPU saving feature from enabling.
Even a noise generator at -200dB prior to the BC plugin is enough to disable CPU saving, and it appears even after the noise is eliminated the CPU saver doesn't engage again until the BC plugin is reloaded.
A single click to set the input silence threshold without manually adding/setting gates all the time is definitely a time/complexity saver. It could be as easy as an invisible gate prior to all other processing where the threshold is set a few % above the input (to prevent unwanted opening closing if the noise amplitude modulates slightly). Definitely worth exploring.
I'm curious: If I load Patchwork up as a VST3 and use it to load up a VST2 synth, does that synth now perform as if it was a native VST3 synth in regards to, say, being automatically suspended in Cubase when not in use?
If you can't dazzle 'em with brilliance, baffle 'em with bullshit.