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?
backupd
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.
Time Machine backups made by Catalina are not compatible with earlier versions of macOS such as Mojave. Here’s how they have changed.
When you find one, bugs will necessarily be multiple. If you think you’ve found one, you can be fairly confident that you’ll find more. Four bugs in macOS for the price of one.
Adds support for local snapshot statistics, Dark Mode, fixes a bug, and is now notarized for your added security.
Detailed comparison of how Time Machine backs up HFS+ and APFS volumes, including its use of local snapshots, with diagrams.
Found in Sierra, but seems to have fallen into disuse, and not found in High Sierra.
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