Sleep, shutdown and battery
MSL freezes every instance before your Mac sleeps, shuts down, logs out or runs out of battery.
On this page 3 sections
A virtual machine that's writing to its disk when the power goes is how Linux disks get damaged. So whenever your Mac is about to sleep or stop, MSL's first move is to freeze every running instance — near-instant, with no disk activity — so none of them is mid-write. Only then does it do anything slower.
What happens when#
| Your Mac… | MSL… |
|---|---|
| Sleeps (lid closed, Apple menu ▸ Sleep) | Freezes every instance. They stay in memory. |
| Shuts down or restarts | Freezes every instance, then hibernates each one to disk. |
| Logs out | The same as shutting down. |
| Is on battery at 10% or below | The same as shutting down, before the battery gives out. |
| Switches to another user | Nothing — instances keep running for you, like everything else in your session. |
MSL never holds up your Mac shutting down.
Waking up#
After your Mac wakes:
- Instances that were frozen stay Suspended until something uses them — open a shell or an app, or click Resume.
- Open terminal sessions have ended — the connection didn't survive the sleep. The Terminal tab shows "Session ended"; click Reconnect.
- MSL corrects the clock of instances that are running, since a frozen instance's clock stops while your Mac sleeps.
Shutting down#
Shutdown, restart and logout hibernate every running instance, so next time you start one it picks up exactly where it was.
Before that, MSL asks open Linux apps to close, the way their own close buttons would — so an app with unsaved work gets its chance to ask.