ASIF disk images are new in Tahoe, and promise to be space efficient, as they’re sparse files, and almost as fast as the disk they’re stored on. Ideal for VMs and general use.
Disk Utility
If you’ve got large files like Virtual Machines or media libraries on the Data volume on your Mac’s internal SSD, use this method to keep the size of its snapshots smaller.
From their use to replicate floppy disks in manufacture, to their key roles in macOS, for distribution of software, and on network servers to contain backups. Unglamorous but essential.
What disk checks are made in Safe mode? How are they different from those run during normal startup? If Disk Utility is to be our only APFS repair tool, shouldn’t have more and better features?
When it started up after its macOS update, available space on its internal SSD had shot from about 160 GB to nearly 400 GB. Where had all my files gone?
The bar chart in Storage Settings shows most of your startup volume is full of System Data. What does it mean, and what use is it? Is its measure of used and free space accurate?
You’re in a rush to eject an external disk, but the Finder tells you it’s in use by unnamed apps. What should you do next, and what has Sloth to do with it?
How snapshots are created from a volume in around 0.01 second, why they will grow in size over time, how they can only be of complete volumes, and can’t be edited.
What separates System and Data volumes, and how does macOS know they’re part of a boot volume group? What distinguished backup volumes, and what is Sidecar?
How to tell whether someone has been eating the (APFS) porridge on one of your disks, using Get Info and DiskUtility’s First Aid. And a surprise hidden volume from 3 years ago.
The Eclectic Light Company 