In short
It works only while you’re away.
What it does to your machine
- It serves only while you’re away, and stops within 47–151 ms of a touch (one Mac, in our tests). The model stays loaded, so it can start again when you leave.
- When a game or a video app needs the graphics chip, it lets the model go: 4.9 s after another app began loading it, in our test.
- It serves again only after you, the graphics chip and the memory have all been quiet for five minutes.
- A laptop serves only while it’s on mains power.
- The engine runs in a sandbox that can’t open your home folder, Documents, the keychain or
~/.ssh, and can’t reach the internet by itself.