Apple file system file system (apfs): all the information

At WWDC 2016 Apple surprised us by introducing a new file system called APFS (Apple File System). This new file system comes to replace the HFS + file system (introduction date 1998), which along with its predecessor HFS (introduction date 1985) are more than 30 years old.

Apple File System file system (APFS)

The idea of ​​Apple is that this file system begins to be implemented with its new Mac OS Sierra operating system in 2017, it seems that in the versions for developers of the new Apple operating system it is already being included, although with some limitations, Please note that the file system is still under development.

This file system will include the following general characteristics:

Apple File System: 64-bit Inodo numbers

APFS supports 64-bit Inodo numbers, which is better than HFS + 32-bit file IDs. Which will mean in a 64-bit operating system that APFS supports more than 9 quintillion files in a single volume.

Extensible Block Mapper

APFS has an expansive block mapper, allowing for more storage on a single device. When initializing very large disks with HFS +, this file system was severely limited by allocation block size and initializes all file system storage on creation. Instead, APFS will create the necessary data structure in a " dynamic " way, thus improving performance.

Scattered files

Apple File System will support sparse files, which HFS + and HFS do not support. Sparse files are a type of computer file that tries to use file system space more efficiently. This is accomplished by writing brief information (metadata) representing the empty blocks on the disk instead of the actual "empty" space that constitutes the block, thus using less disk space.

Disaster protection

APFS uses a novel metadata system called " Copy-on-Write " that ensures file system updates against disasters (for example, in case the power goes out when the hard disk is writing or reading data). This approach also reduces the additional overhead that occurred with HFS +.

Extended attributes

Apple File System has been designed to support extended file attributes. In HFS + this functionality already existed with the file attributes, but it seems that they have redesigned it.

TRIM operation

Like HFS +, the Apple File System will support TRIM operations. In APFS, TRIM operations are issued asynchronously so that since a file is deleted or space is freed, it is recovered, thus ensuring that metadata is only changed once, thus preserving storage stability.

Encryption

One of the things that have been fundamental in the design of Apple's new file system has been security and privacy. In OS X full disk encryption is available from OS X 10.7 Lion and in iOS encryption is for each individual file from iOS4. APFS combines these two modes in a unified model that encrypts the file system metadata. APFS supports encryption natively. Being able to choose between the following encryption models in each volume:

• Unencrypted. Encrypted with a single key. Multi-key encryption with keys for each file and a separate key for sensitive metadata. In this way we ensure the integrity of user data, even when physical security is compromised.

WE RECOMMEND YOU Apple would have to pay $ 7 billion to Qualcomm. Encryption uses either AES-XTS or AES-CBC technology, depending on the hardware.

Compatibility

• Some of the third party applications will need to be updated to support APFS. Volumes formatted in APFS will not be recognized in OS X 10.11 El Capitan and earlier. You will be able to share the volume formatted using the SMB file sharing protocol.

Along with these features Apple File System will add some new features or improvements:

Flash / SSD optimization

APFS will optimize Flash / SSD storage and can be used with traditional hard drives. To do this, it will use a new type of copy-by-write, the Copy-On-Write that we talked about above, which maximizes the performance and at the same time the reliability of the data.

Shared space

A new approach to how to take up space on your hard drive, related to sparse files.

Cloning of Files and Directories

A new approach in that different revisions of files and directories do not take up so much space on the file system.

Snapshots

A snapshot is a read-only instance of a volume's file system. The operating system will have the ability to make snapshots to make backups that will make programs like Time Machine more efficient.

Quick calculation of Directories size

Quick directory size calculation allows APFS to get the total used space faster.

Atomic Safe-Save

Apple File System introduces a new transaction called Atomic Safe-Save that allows safe saving of packages and directories. This operation will be invisible to the user.

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