Apple File System

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Apple File System (APFS)
Manufacturer Apple
Full name Apple File System
Initial release March 27, 2017 (iOS), September 25, 2017 (macOS) ( iOS 10.3 , macOS 10.13 )
Partition identifier 7C3457EF-0000-11AA-AA11-00306543ECAC ( GPT )
Technical implementation
Directories B-tree
Maximum values
Size of a file 8 egg (2 63 bytes)
Number of all files 2 63
Allowed characters in the file name Unicode 9.0 encoded in UTF-8
properties
Dates of a file Creation, content change, attribute change, last access
Date range Jan. 1, 1970 - July 21, 2554
Forks supported
File rights management Unix permissions, NFSv4 ACLs
Transparent compression Yes (decmpfs)
Transparent encryption Yes
Copy-on-write Yes
Supporting operating systems macOS , iOS , iPadOS , tvOS , WatchOS

The Apple File System (APFS) is in June 2016 Apple as the successor to HFS + imagined filesystem .

At first, the file system was only available for iOS . The first official use of APFS on mobile devices was announced on March 27, 2017 with iOS version 10.3. In Mac OS, APFS was implemented from version 10.13 High Sierra .

New function

APFS is optimized for the use of flash memory such as SSDs , but can also be used with conventional hard drives.

" Space sharing " allows several logical drives to share the storage space on the same physical drive. Each APFS container has the entire available memory of the physical drive available. Example: An APFS container with a size of 100 GB contains two logical drives: A (10 GB) and B (20 GB used). The free space of both drives A and B is specified as 70 GB (100 GB - 10 GB - 20 GB).

APFS drives can be dynamically resized without having to repartition the drive.

Clones are copies of files or directories that are immediately available and require no additional space ( copy-on-write ). When cloning, only the directory entry of a file is copied. When changing a cloned file, only the changed blocks are additionally written to the drive. This allows the file system to hold different versions of a file and it takes up little additional space.

Snapshots are read-only instances of a file system on a drive. They help to create data backups efficiently and offer the possibility of rolling back changes to a specific point in time.

" Fast Directory Sizing " allows APFS to quickly calculate the memory consumption of a directory structure and keep it up to date.

" Atomic Safe-Save " executes renaming in a single transaction in such a way that, from the user's perspective, an operation has either been carried out completely or does not happen at all.

APFS supports the encryption of entire volumes, individual files and sensitive metadata. It supports the following encryption methods:

  • Single key encryption
  • Multi-key encryption with per-file keys for data and a separate key for sensitive metadata. Multi-key encryption ensures the integrity of user data. Even if someone compromised the physical security of the device and gained access to the device key, they would not be able to decrypt the user files. Apple File System uses AES- XTS or AES-CBC encryption modes, depending on the hardware.

APFS provides more space available.

restrictions

As of September 2017, the following restrictions apply:

See also

Web links

Individual evidence

  1. a b K.H. Hansen, F. Toolan: Decoding the APFS file system . In: Digital Investigation . 22, September 21, 2017, ISSN  1742-2876 , pp. 107-132. doi : 10.1016 / j.diin.2017.07.003 .
  2. a b Volume Format Comparison ( en ) Retrieved May 25, 2018.
  3. a b Apple File System Guide / Frequently Asked Questions . Retrieved May 25, 2018.
  4. ^ René Bertin: Compression and APFS . Retrieved December 13, 2019.
  5. a b Apple Inc: Apple File System Guide (Features) . Retrieved May 25, 2018.
  6. Leo Becker: iOS 10.3 is here: Apple brings new file system APFS to iPhone and iPad. In: heise.de. March 27, 2017. Retrieved July 24, 2019 .
  7. Apple introduces HomePod, iOS 11, new iPad Pro and iMac Pro. In: derStandard.at. Retrieved June 7, 2017 .
  8. a b Bastian Gruber, Mark Zimmermann: High Sierra: What APFS, HEVC and HEIF bring. September 27, 2017, accessed December 6, 2018 .
  9. Apple File System Guide. In: Apple Developer Documentation , accessed September 22, 2017.
  10. APFS is also available for hard drives and Fusion-Drive-Macs In: Heise.de - Mac & i, accessed on June 28, 2018.
  11. Disks you can use with Time Machine In: Apple Support , accessed June 13, 2018. (English)