Get more information about background processes from Activity Monitor, the command tool sfltool performing a BTM dump, attributions.plist, and the log.
background
From a simple linear Basic program, or a command tool like tar, to working with macOS to get threads allocated to the most appropriate cores and run at the right frequency.
After logging in, macOS may check for system software updates, run an initial Time Machine backup, and run XProtect Remediator scans. This is how those happen.
Spotlight indexes on-the-fly so new and changed files are quickly searchable, but periodically needs to assimilate those into its more static indexes. That and Live Text extraction are run following startup.
How to control Login and Background items in System Settings, how to identify those you might not recognise, and how to use sfltool for advanced diagnostics and reset.
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.
Easy to code, these don’t need to use XPC although it’s used by the DAS-CTS scheduling and dispatch system. They aren’t run at constant time intervals, but when appropriate according to other loads.
How does XProtect Remediator scan your Mac once a day? What has gone wrong when it doesn’t appear to work? Explained from its property lists to its three different types of scan.
There’s normally more than 500 background activities, like Time Machine backups and XProtect Remediator scans, waiting for dispatch in the list maintained by DAS. How this works.
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