Performance & battery · Staying light on your Mac
How much of my Mac's processor and memory is Storage Studio allowed to use?
Short answer: Storage Studio limits its background work to a share of your Mac's free processor and memory, not of the whole machine. The share depends on the performance mode and shrinks further while you're working or on battery.
Storage Studio caps its background work to a share of what your Mac has free at that moment — never a share of the whole machine. On a busy Mac with little spare, that share is tiny; on an idle Mac it can work a bit faster and finish sooner.
How big that share is depends on the performance mode. The everyday modes keep it small, Light keeps it smaller still, Survival pauses background work entirely, and Extreme — which you have to choose yourself — lets background work use more of the spare capacity so it finishes sooner.
On top of the mode, the budget shrinks further while you're actively typing or clicking, and when you're on battery.