Irregular Time Machine backups are one of Sierra’s great mysteries. It now looks as if they might have been fixed in 10.12.4.
launchd
Schedule a periodic task as a Launch Agent. How close to the expected time does macOS actually run it?
This command tool can now write just the integer passed to it as a log message. This is ideal for instrumenting scripts and apps for analysis.
macOS Sierra doesn’t run periodic backups using a simple mechanism. Here’s the story in full detail.
Working out why Time Machine backups go wrong isn’t necessarily that different from unravelling classical mythology. In some ways.
Getting deeper into using Sierra’s new logs, and investigating why Time Machine backups become irregular.
Does macOS scheduling fail when it has been running for more than 10 days? Irregular backups suggest that it does.
Please post comments adding to this list if you think you have found a bug, so that others can be aware too.
How to understand Console’s log entries for a normal shutdown, and a normal startup.
If the kernel is the heart of OS X, launchd is its brain. Use it to run periodic tasks such as synchronising folders automatically.
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