Mac frozen with the spinning beachball — what to do

The cursor turns into a rainbow pinwheel — what older Mac users still call the “spinning beach ball of death.” It means a process is blocked: waiting on disk, on network, on a mutex, on something. The whole Mac isn’t frozen; just one app is unresponsive. You can usually fix it without restarting.

What’s actually happening

When an application’s main thread is busy or waiting and doesn’t service the event loop for two seconds, the system replaces the cursor with the spinning beachball over that window. Everything else on the Mac keeps working. If the whole UI is unresponsive, that’s a different problem — usually severe memory pressure or kernel-level disk contention.

Find the stuck process

1. Try cmd+tab to another app. If you can switch and the new app responds, only the original app is frozen. Confirmation that the Mac itself is fine.
2. Open Activity Monitor. Frozen apps show up red with "(Not Responding)" next to the name.
3. Select the frozen process and click the X button (top-left). Choose "Force Quit." This is the equivalent of kill -9 PID.
4. If Activity Monitor itself is slow, use Terminal. Run top -o cpu or ps aux | grep -i [appname] and use kill -9 PID.
5. If everything is frozen, check memory pressure. Long beachballs across all apps usually mean the Mac is swapping hard. Try waiting 30 seconds before forcing a restart.

Why beachballs happen

Common causes in order of frequency: the app is waiting on a slow network response (the saved-file dialog enumerating an SMB share is notorious), the app is waiting on disk I/O while another process is hammering the SSD, memory pressure is forcing the app to swap pages in from disk, or the app has hit a bug and is stuck in a loop.

Diagnose the cause

If beachballs happen often:

• Check Activity Monitor’s Disk tab during a beachball. If sustained writes are 100+ MB/s from another process (Time Machine, Spotlight, a cloud sync), that’s your starvation.
• Check memory pressure. If it’s yellow or red regularly, you’re hitting swap and beachballs will be frequent.
• Check Console for crash logs and hangs reports under ~/Library/Logs/DiagnosticReports/.

Catching it in the act

The challenge with beachballs is they often hit before you’ve opened Activity Monitor. By the time you’ve launched it, the cause has moved on. A persistent menubar monitor shows the I/O or memory spike at the exact moment of the beachball, so you can correlate cause and effect.

Beacon keeps disk I/O, memory pressure, CPU and network in the menubar — $14.99 lifetime. Download Beacon if you want continuous visibility instead of post-hoc reconstruction.

If you’re getting beachballs every day on the same app, that’s a bug report waiting to happen. File it.