This workflow enhancer is really simple.
Just disable VST plugins during times in tracks when they are not being used.
Automate the nifty device activator (aka “on/off switch“) of a device (or a rack of devices) to shut off during times of silence. Set the automation to switch on a little bit before audio starts, and to turn back off a bit after the audio is completely silent again.
Automating device activators this way as a go-to workflow prevents pointless excessive CPU usage which would otherwise tax the system to no benefit. When working with large projects that contain lots of tracks with lots of plugins, economizing CPU anywhere possible can be very helpful.
Following this technique can also greatly speed up freezing tracks. Instead of taking the time to process the silent times during the frozen track, your DAW will instead go over those areas much more quickly, resulting in the freeze being accomplished sooner, allowing you to get back to work more swiftly. The amount of time gained depends on how many and what type of plugins are bypassed. This strategy is particularly helpful for very lengthy tracks, or when working on a deadline.
Prevent all those plugins from doing their work during silent spans of time!
What about AU and Ableton Native effects? Or VST3? As far as i know, these both avoid processing when not required on their own—so the CPU is basically automatically disabling itself for you when not needed, and so these formats are not as much of a concern as VST2 is. Caveat: this might not be true for certain plugins that do things like constantly generate low-level noise, which presumably process whether or not there’s audio passing through them.
I hope that this simple workflow enhancer is helpful to you.