How DAS gathers its budgets and loads lists of activities. When rescoring permits, it then dispatches the process to initiate backup. Re-scheduling has changed in Sequoia, as shown here.
backupd
How to use the Time Machine log extract in Mints to check whether its backups are working normally, and what are expected errors.
Detailed account and explanation of the sequence of phases during an automatic backup in Sonoma 14.0 and 14.1, with tear-out chart.
First released 16 years ago, it was destined for Time Capsules, and relied on hard links in HFS+. It soon used APFS snapshots, and now uses them as the basis for its backups.
Detailed account from the decision to start making an automatic backup to its final reporting and completion, for Ventura 13.2.1 to local storage.
Can you get Time Machine to back up faster by turning I/O throttling off? If so, it this something to do only for large backups, or can it be set as the default? Does it also affect other background processes?
Why Time Machine makes snapshots, and how they can grow and apparently consume free space. What you can and should do to manage this.
Is it overhead from sandboxing, the file system, the throttling of I/O, or the limitations of the Efficiency cores? Is there anything a user can do?
How the start of Time Machine backups to APFS volumes is scheduled and dispatched, and a fascinating Secure Backup Daemon.
How Time Machine has changed since it appeared in 2007, and how backing up to APFS volumes is different now it’s available in Big Sur.
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