Back in November 2021, macOS Monterey had a nasty surprise waiting for early adopters: a widely reported memory leak that let everyday apps balloon to tens of gigabytes of RAM. Users watched Control Center, Safari, and Mail swallow their memory whole until macOS threw up the dreaded “Your system has run out of application memory” alert. Both Intel and Apple Silicon Macs were affected. Here’s what was actually leaking, the workaround that helped, and how it was finally fixed – plus Activity Monitor skills that are still useful today.
What was eating the RAM?
On Monterey 12.0 and 12.0.1, several system and third-party processes could grow without bound. The worst offenders, per MacRumors and 9to5Mac reporting at the time, were Control Center, Safari, Mail, Firefox, and Pages – any of which could reportedly consume 20, 40, even 80 GB of RAM on machines with a fraction of that physically installed. Once swap was exhausted, the system ground to a halt.
The confirmed trigger: brightness + HDR
Community sleuthing pinned down one reliable trigger: Control Center’s memory footprint grew every time the display brightness was adjusted while HDR content was on screen. Each nudge of the brightness slider leaked a chunk of memory that was never freed. The mitigation, until Apple shipped a fix:
- Disable auto-brightness. Go to System Preferences – Displays and uncheck “Automatically adjust brightness”.
- Avoid the brightness slider during HDR playback. If you’re watching HDR video, set brightness beforehand and leave it alone.
Immediate relief: use Activity Monitor
- Open Activity Monitor. Find it fast – see how to quickly open the installed apps list on macOS – or press Command + Space and type its name.
- Click the Memory tab and sort by the Memory column to see the biggest consumers at the top.
- Select the runaway process and click the X (stop) button to force-quit it. Control Center, for example, relaunches itself automatically.
Warning: do not casually force-quit WindowServer – your screen will go black and you’ll be dumped back to the login screen. Stick to the actual leaking app.
The lasting fix: update macOS
Apple addressed the leak in macOS 12.1 (December 2021) and subsequent updates. If you’re still on 12.0 or 12.0.1 for some reason, updating is the real fix – the workarounds above were only ever stopgaps. Check Apple Support for the latest macOS update available for your Mac.
If it still doesn’t work
- High memory use on a modern macOS – this specific leak is history; today’s culprits are usually browser tabs or Electron apps. Activity Monitor still finds them the same way.
- Can’t update past Monterey – check whether your Mac supports a newer release before assuming you’re stuck.
- Leak returns after reboot – look for login items or menu-bar utilities that re-trigger the old behavior.
Frequently asked questions
Did the Monterey memory leak affect M1 Macs too?
Yes. Reports covered both Intel and Apple Silicon Macs – the bug was in macOS itself, not the chip architecture.
Is it safe to force-quit Control Center?
Yes – macOS relaunches it automatically, which is exactly why it was a handy temporary fix: the fresh instance started with a clean, small memory footprint.
Conclusion
The Monterey memory leak is a solved problem – update to 12.1 or later and it’s gone. But the episode left every Mac user a useful skill: reading Activity Monitor’s Memory tab. And while you’re keeping your Mac healthy, see how to set up automatic hotspot connection from iPhone on Mac.
