{"id":42316,"date":"2017-09-15T22:02:04","date_gmt":"2017-09-16T03:02:04","guid":{"rendered":"https:\/\/eshop.macsales.com\/blog\/?p=42316"},"modified":"2018-08-02T10:07:50","modified_gmt":"2018-08-02T15:07:50","slug":"update-macos-high-sierra-and-apfs-compatibility","status":"publish","type":"post","link":"https:\/\/eshop.macsales.com\/blog\/42316-update-macos-high-sierra-and-apfs-compatibility\/","title":{"rendered":"Translating Apple’s New High Sierra & APFS Compatibility Document"},"content":{"rendered":"
\"Apple
(Apple File System.)<\/strong><\/figcaption><\/figure>\n

[UPDATE:<\/strong> Tim Standing, VP of Software Engineering for OWC Holdings Inc., takes a deep dive into APFS<\/a>]<\/strong><\/p>\n

Thanks to sharp-eyed Rocket Yard commenter Chris pointing us to an Apple support document, we now have a bit more information on macOS High Sierra<\/a>, Apple File System<\/a>, and how it all works on Macs and on volumes that are formatted with the legacy HFS+ file system.<\/p>\n

[NOTE: At the request of several readers, we’ve added some “translations” to the Apple document listed below to make it more understandable.]<\/strong><\/p>\n

Chris pointed us to this Apple tech document, titled Prepare for APFS in macOS High Sierra<\/strong><\/a>. Probably the most important information from Apple is this quote:<\/p>\n

Apple File System (APFS) is the default file system in macOS High Sierra for Mac computers with all-flash storage. APFS features strong encryption, space sharing, snapshots, fast directory sizing, and improved file system fundamentals.<\/i><\/p>\n

When you install macOS High Sierra on the built-in solid-state drive (SSD) of a Mac, that drive is automatically converted to APFS. Fusion Drives and hard disk drives (HDDs) aren’t converted. You can’t opt out of the transition to APFS. <\/strong>(Rocket Yard emphasis)<\/i><\/p>\n

So basically, if you install APFS on any<\/em> Mac that uses a solid-state drive as a built-in boot drive, it will automatically convert to APFS and you will not have a choice. Those Macs that use Fusion Drives (like the iMac, for example) or good old hard disk drives will not<\/em> be converted, period. [UPDATE 09\/25: Apple software engineering chief Craig Federighi has confirmed APFS will indeed be coming to Fusion Drives<\/a> in a later update.]<\/strong><\/p>\n

Here is the rest of the technical note verbatim, with our translation of Apple’s writing in italics:<\/p>\n

\n

APFS compatibility<\/strong><\/p>\n

Devices formatted as Mac OS Extended (HFS+) can be read from and written to by devices formatted as APFS.<\/p>\n

Translation: You can read and write to disk drives that were formatted as HFS+ from a Mac with a boot drive formatted as APFS.<\/i><\/p>\n

Devices formatted as APFS can be read from and written to by:<\/p>\n