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Apple Introduces New File System AFPS With Tons Of 'Solid' Features (apple.com)
On the sidelines of its Worldwide Developer's Conference, Apple also quietly unveiled a new file system dubbed APFS (Apple File System). Here's how the company describes it: HFS+ and its predecessor HFS are more than 30 years old. These file systems were developed in an era of floppy disks and spinning hard drives, where file sizes were calculated in kilobytes or megabytes. Today, solid-state drives store millions of files, accounting for gigabytes or terabytes of data. There is now also a greater importance placed on keeping sensitive information secure and safe from prying eyes. A new file system is needed to meet the current needs of Apple products, and support new technologies for decades to come.Ars Technica dived into the documentation to find that APFS comes with a range of "solid" features including support for 64-bit inode numbering, and improved granularity of object time-stamping. "APFS supports nanosecond time stamp granularity rather than the 1-second time stamp granularity in HFS+." It also supports copy-on-write metadata scheme which aims to ensure that file system commits and writes to the file system journal stay in sync even if "something happens during the write -- like if the system loses power." The new file system offers an improvement over Apple's previous full-disk encryption File Vault application. It also features Snapshots (that lets you throw off a read-only instant of a file system at any given point in time), and Clones. According to the documentation, APFS can create file or directory clones -- and like a proper next-generation file system, it does so instantly, rather than having to wait for data to be copied. From the report: Also interesting is the concept of "space sharing," where multiple volumes can be created out of the same chunk of underlying physical space. This sounds on first glance a lot like enterprise-style thin provisioning, where you can do things like create four 1TB volumes on a single 1TB disk, and each volume grows as space is added to it. You can add physical storage to keep up with the volume's growth without having to resize the logical volume.As the documentation notes, things are in early stage, so it might take a while before AFPS becomes available to general users.
This new filesystem should become stable in about 2028.
I'm glad Apple has introduced this. As of now, the snapshot API and others are not present, but now Apple is on parity with everyone else in the industry.
APFS isn't like ZFS or btrfs, but more like ReFS in the fact that it still requires a logical volume manager. It would be nice if it had RAID, but that is a minor item, compared to just getting rid of HFS+, which just had to be killed.
Some features I like:
The ability to encrypt volumes with multiple volume keys. It looks like it will be similar to Oracle's ZFS on Solaris, but the implementation can be completely different.
Snapshots. Something like zfs send and zfs send -i will be quite useful for backups.
Copy-on-write capability, which is useful for VMs.
Of course, it appears that Apple will be documenting and publishing the FS's specs in 2017, which will be even more useful for compatibility.
All and all, even though there is no RAID 5/RAID-Z, or LVM replacement, this is a heck of a lot better than what OS X/macOS has now.
Licensing. Apple did flirt with ZFS, but for some reason, and I would guess it was license issues, they decided not to go that route. Using btrfs would bring GPL/BSD licensing issues. So, Apple either had to license something like ReFS from MS, or roll their own.
Swift 2 is stable enough that I get occasional calls from recruiters asking for five years of it as a language for dev jobs. So, if it is good enough to transcend time/space, it should be stable enough.
ZFS is under CDDL and would not even need to be "licensed" in the usual sense — it is free for anybody to take. "Too free" for certain zealots, in fact, which is why it was not part of Linux kernel for a while — until the supposed "license incompatibility" myths got debunked.
Even Linux now offers ZFS — Apple would've had a much easier time porting it, because MacOS is already FreeBSD-based and the FreeBSD-project had ZFS available "out of the box" for several major releases spanning many years.
What did Apple find lacking about ZFS, that would justify creating their own, is, indeed, a mystery. Probably, a case of the Not Invented Here Syndrome. Sad...
In Soviet Washington the swamp drains you.
Would you want to be licensing anything from Oracle today?
I was hoping Apple would license ZFS or even Veritas Volume Manager/Veritas FS from Symantec.
I thought Veritas was also called Online Journaled File System (OnlineJFS or OJFS). What else is OJFS?
OJFS? Why do you computer types insist on naming your filesystems after murders?
What a ridiculous argument.
By that logic, backwards compatibility is never an issue. Why even try to offer it? You can just keep using the old version! Compatibility solved!
ZFS is not recommended for non-ECC RAM. RAM errors can get propagated to disk by application read operations, not just writes.
http://research.cs.wisc.edu/ad...
What kinds of files are people generating today? Pictures and video. What kinds of files are already compressed to begin with? Pictures and video. Compression doesn't make sense unless you have massive amounts of text or database files.
Only the State obtains its revenue by coercion. - Murray Rothbard
Having occasionally yanked out removable media on OS X without properly ejecting it, you can do so now. But you run the same risks as every other OS and commonly-used filesystem: that things will be corrupted in the process and have to be fixed the next time you insert the drive.
What are these "other OS" you speak of? Windows? No. It will happily corrupt files depending upon what you are doing with the drive in question at the time you yank it out. Likewise Linux and most of its filesystems. Modern journaled filesystems are likely to be able to put things back into some semblance of order in the aftermath, but if you think it is routine to be able to do this without special setup you are mistaken.
The only thing I've noticed is that Windows will complain less frequently when you yank out a device, whereas OS X will reliably and correctly warn you that doing so is dangerous and not recommended unless you eject it in software first. In fact, OS X is better at informing you which program has files open on the device when you attempt to eject it, whereas Windows will just vaguely tell you that something is still holding up the process. Oh, and Windows "helpfully" disables write caching to slow down your pluggable devices in an attempt to diminish the likelihood you'll corrupt something. Whether you consider that truly helpful or not is debatable. It's a significant tradeoff.