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.
startup
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.
Apple silicon Macs may not obtain an external reference time for many seconds after starting up. Do they adjust their local clock over that period, and if so, against what reference?
You’re sometimes advised to shut your Mac down, wait a while, and start it up again, instead of restarting it. Are they different, and if so when should you use them?
Security services including TXM, Core Crypto, AMFI, Credential Manager and the SEP Key Store, Gatekeeper and AppleSystemPolicy, tracked during startup.
Are you worried about your Mac maxing out its E cores after starting up in Sequoia? There may be nothing wrong about this, as explained here.
Simply having a boot volume group with a System snapshot in it won’t get your Mac to start up from that disk, particularly if it’s an Apple silicon model. Some details.
When you start your Mac up, the fans blow full on, and you see CGPDFServices taking lots of CPU %. Is this malware? No, but it’s new in Sonoma.
Sometimes, a cold boot fixes problems not fixed by a simple restart. Why, and which problems is it better at fixing?
What to do when your Mac panics during booting, and enters a boot loop, or when it simply fails to get to the login window.
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