Comparing ApFS and HFS

Developer.apple.com has published a comparison of file systems' volume formats:

Mac OS Extended (HFS+) Apple File System (ApFS)
Number of allocation blocks 2 32 (4 billion) 2 63 (9 quintillion)
File IDs 32-bit 64-bit
Maximum file size 2 63 bytes 2 63 bytes
Time stamp granularity 1 second 1 nanosecond
Copy-on-write
Crash-protected journaled
File and Directory clones
Snapshots
Space sharing
Native encryption
Sparse files
Fast directory sizing
Since ApFS is optimized for SSD, the speed of access to the flash media will be higher than when using HFS+.

On hard drives performance gains will be minimal. We conducted tests with a regular hard drive, here are the results:

FS READ WRITE READ (IOPS) WRITE (IOPS)
HFS 85.15 85.37 81.2 81.4
ApFS 85.29 85.98 81.3 82
OpenZFS 58.45 28.52 56 41