Although not discussed in today’s keynote, Apple is adding a new “universal” filesystem to iOS and macOS. Apple File System (APFS) will likely replace HFS+ as the default filesystem for Macintosh computers, iPads, and iPhones and brings a wealth of modern features. But judging from the initial developer documentation, that’s not going to happen for a few more years. And there’s still much confusion about how APFS and CoreStorage, introduced in Mac OS X 10.7, will interact.
This morning, Apple introduced the new iMac, with a build-to-order storage configuration called “Fusion Drive”. But what is Fusion Drive? Although it could be an off-the-shelf hybrid drive, I believe it is a software driver in Mac OS X.