Large downloads don't survive sleep
14 GB macOS update. 90 GB game from Steam. Batch of video files from Google Drive. You walk away, Mac sleeps, and when you come back the download is either paused or completely dead. Starting over from scratch.
macOS kills the Wi-Fi radio when it sleeps. Connection drops, and the server on the other end either waits (if you're lucky) or closes the connection. Big files that take hours only need one sleep event to ruin the whole thing.
Why your browser won't save you
Some apps ask macOS to stay awake while they're working. Plenty don't. Safari, Chrome, Firefox all let macOS sleep mid-download without complaint. So does the Mac App Store when pulling large updates.
Resumable downloads help when they work. But not all servers support HTTP range requests, and not all apps handle resume correctly. Torrent clients are usually fine since they're built for interruption. A straight HTTP download from a CDN? Coin flip.
The fix: Shake It On with the right conditions
Shake It On keeps your Mac awake with mouse movement. For downloads, two conditions do the job:
- Paused When on battery. Unplug your MacBook and shaking stops. You don't want a forgotten download draining battery to zero overnight.
- Only Shake If Wi-Fi connected. No network, nothing to keep alive. Shake It On pauses until you're back online.
Both on, and Shake It On keeps your Mac up while you're plugged in and connected. Either condition changes, it backs off. Nothing to remember.
Pro tip: pair it with Allow display to sleep
Leaving a download running overnight? Screen doesn't need to be on. Turn on "Allow display to sleep" in Shake It On. System stays awake, download keeps going, display dims on its normal schedule. Download finishes, screen isn't wasting power, Mac sleeps normally once conditions clear.