How macOS schedules tasks like making automatic Time Machine backups, from property list to transactions between DAS and CTS.
cron
The story of how Mac OS X went from cron, to launchd, and ended up with Duet Activity Scheduler, to schedule background activities like backups.
How to set your Mac to run scripts, apps and other software automatically, and at regular intervals, using launchd and a property list.
Prior to 10.4, Mac OS X used cron, then scheduling became part of the job of launchd. Later Apple added a new subsystem, Duet Activity Scheduler, which continues to evolve.
What does it take for an app to have ‘activities’ managed for efficiency by CTS? Not a lot – but in return, the management is a black box.
In the first article in this series, I explained how a great many background activities in macOS, including […]
Rather than using cron or launchd, many background services in macOS are now run using Centralized Task Scheduling (CTS). This is how it works.
Scheduling background activities like making backups has moved from cron to launchd, and now to a more complex system. This has reduced the reliability of macOS and made it harder to support.
Background activities scheduled by third-party software currently use launchd, and run the risk of affecting the user. Would GCD be a better choice of dispatcher?
Schedule a periodic task as a Launch Agent. How close to the expected time does macOS actually run it?
The Eclectic Light Company 