Deciding which file system to use for hard disks can be difficult. Here are the advantages and disadvantages explained in detail, for HFS+ and APFS.
HFS+
First securing the Home folder in an encrypted sparse disk image, then to whole-volume encryption using CoreStorage, now using T2 and Apple silicon chips.
When do sparse files explode to full size, and how could you preserve them in transit? Can you copy clones or snapshots? How to preserve extended attributes?
APFS or HFS+? Which can Time Machine back up to? What about hard disks? Which format for use on PCs? And which are supported by Disk Utility now?
macOS has an elaborate set of rules determining which types of xattr are preserve during different types of copying, including syncing to iCloud Drive. Here they are in full detail.
Extended attributes were added to Mac OS X 10.4, and soon supported the quarantine xattr. They have since flourished, and have valuable properties.
Released in Mac OS X 10.5 Leopard on 26 October 2007, it supported Time Capsules launched in January 2008, and in Big Sur could back up to APFS.
Originally two separate apps, they were brought together in Mac OS X, and have survived largely unscathed to Sequoia. Here are some highs and lows to remember.
Sparse files are now common among databases, disk images, and virtual machines. How they work in APFS, how they’re created, and how they can explode.
Classic TM backed up HFS+ to HFS+; current TM backs up APFS to APFS. But what if you want to back up a mixture of APFS and HFS+ volumes?
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