Is it safe to delete Xcode parallel testing clones?
Copies of simulators that Xcode makes so tests can run on several simulators at the same time.
Safe
Its owner recreates it by itself when it needs it, and nothing you made is lost.
~/
What it is
When you run tests in parallel on a simulator, Xcode clones the simulator you chose several times and runs part of the tests on each clone. The clones live here, separate from your own simulators, and clones from earlier test runs can stay behind. Xcode makes new clones the next time you run tests in parallel.
If it's removed
The next parallel test run takes a little longer to start while Xcode makes new clones. A test run that's in progress stops.
How it's removed
Xcode's own cleanup command (xcrun simctl --set testing delete all), run by the app. Quit Xcode first.
The free analyzer finds it and explains it. Removing it is Pro, after a review sheet that lists every move and command. It starts checked in the Cleanup checklist, except inside Documents or Desktop.
Sources
- devstreaming-cdn.apple.com/videos/wwdc/2018/403r3eh2u29dfeml/403/403_whats_new_in_testing.pdf
- github.com/AvdLee/Xcode-Disk-Cleanup-Agent-Skill/blob/main/xcode-disk-cleanup/references/simulators.md
Last checked on 26 Sep 2026. Every entry is written and checked by hand; the app and the command-line tool use the same words.