It’s the percentage of time a core in active, when not idle or shut down. That’s confounded by Intel Hyper-threading, and frequencies of Apple silicon cores.
Apple silicon
Apple silicon architecture is designed to get background processes out of the way of our apps running in the foreground, by using the E cores.
One Thunderbolt port is the designated DFU port, to be used when connecting via USB-C in DFU mode, and to be avoided for external bootable disks. But how can you identify it?
You press the Power button, but nothing happens. Has your Mac suddenly died, does it have a problem you can fix easily, or is it just in DFU mode?
After the Boot ROM, LLB and iBoot (stage 2), kernel boot starts setting up security services and putting the hardware to work. CPU cores are started up before file systems are mounted, and the Mac starts userspace boot.
First decide what you want to ‘clean’: the Data or System volume, or firmware? Then consider the methods of choice to perform that. Explained for Intel and Apple silicon Macs.
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?
Apps supplied through the App Store aren’t signed by their developer, but by Apple. Many now have certificates that have expired. When will they stop running?
Which system and AI cryptexes are loaded during macOS boot? Here are details of the 28 for AI in Tahoe 26.2, and which are new since Sequoia 15.5.
An overview of code signing and certificate requirements to come when macOS 27 is released in a few months, supporting only Apple silicon Macs. How Intel Macs will be affected in the near future.
The Eclectic Light Company 