4 ms·

The spartan description of APFS certainly sounds like the (partial) feature list for ZFS--the comparisons made in the comments here are on-point. ZFS though too

by ahl 10y ago

The spartan description of APFS certainly sounds like the (partial) feature list for ZFS--the comparisons made in the comments here are on-point. ZFS though took around 5 years to ship and, arguably, another 5-10 to get right. I say this having shipped multiple products based on ZFS, writing code in ZFS, and diagnosing production problems with it. On-disk consistency ("crash protection"), snapshots, encryption, and transactional interfaces ("atomic safe-save") will no doubt be incredibly valuable. I don't think though though that APFS will dramatically improve upon the time it took ZFS to mature from a first product to world-class storage. Some commenters have opined that (despite Apple distributing ZFS for Mac OS X at WWDC nearly a decade ago) that ZFS would never be appropriate for the desktop, phone, or watch. True ZFS was designed for servers and storage servers, but I don't think there's anything that makes it innately untenable in those environments--even its default, but not essential, use of lots of RAM. Who knows... maybe Apple have spent the decade since killing their internal ZFS port taking this new filesystem though the paces. Its level of completeness though would suggest otherwise.

watersb 10y ago
Yes. I was a heavy user of ZFS on Mac OS X back then. Was on the developer mailing list for that implentation, submitting bugs and talking to Apple developers working like mad to ship it. Then Steve Jobs' buddy Larry bought Sun, and licensing of ZFS became basically impossible to sort out on time. So they dropped it. Was that 2007 or 2009?
- ahl 10y ago
  The Sun acquisition was announced in 2009 and closed in 2010. It may have been related, but I have my own suspicions about about what caused Apple to jettison their port.
  - rafaelferreira 10y ago
    Do tell.
  - astrodust 10y ago
    Given the mountain of legal shit Google has been subjected to over Java, the last thing Apple wanted was to have to answer to Larry's lawyers. ZFS, awesome as it is, has been poisoned.
  - wmf 10y ago
    It's like no one here remembers the NetApp lawsuit.
- rangibaby 10y ago
  2009. I remember ZFS was coming in Snow Leopard. Then it wasn't /edit https://web.archive.org/web/20080721031014/http://www.apple.com/server/macosx/snowleopard/ https://web.archive.org/web/20080721031014/http://www.apple....
- saithier 10y ago
  The thing that killed ZFS on the Mac was the NetApp lawsuit over it against Sun.
jburwell 10y ago
It's impossible to know how long they have been working on it. As I recall, Swift had been in development for 3+ years before it saw the light of day.
- gh02t 10y ago
  Yeah, I bet it's been in development for a while. People have been seriously bitching about HFS+ for at least a decade, and with good reason. Apple has been pretty much silent about it apart from briefly testing ZFS and I'd wager a guess that they started working on it shortly after they abandoned that, while they continued also bolting more stuff onto HFS+ in the meantime.
mioelnir 10y ago
Between the ZFS-like features and the advertised "novel copy-on-write metadata" scheme, I would not be surprised if it was partially based on DragonFly's HAMMER/HAMMER2 filesystem.
- ahl 10y ago
  It would be a strange kind of NIH that excluded ZFS but welcomed HAMMER...
  - feld 10y ago
    different licensing and HAMMER demands significantly less memory
  - AceJohnny2 10y ago
    Licensing.
    - deleted 10y ago
      [deleted]
- mindajar 10y ago
  If you poke around in the the APFS kernel extension, it's not a very big binary, given the feature set. (It's a 550K extension, compared to the 2.5MB zfs.ko on FreeBSD.) I haven't disassembled it yet, but I'd wager that APFS is layered atop Core Storage btrees/CoW. Since that code's been shipping since 2011, maybe APFS stabilizes faster than a true greenfield filesystem? (That does leave me wondering how interesting an open-source APFS would be without an open-source Core Storage.)
  - Freaky 10y ago
    > It's a 550K extension, compared to the 2.5MB zfs.ko on FreeBSD hammer.ko is 494KB in the latest DFBSD, for those wondering the obvious.
- Wildgoose 10y ago
azinman2 10y ago
Unless I'm misreading, the page seems to indicate that only external volumes can be formatted with APFS. My guess is that they'll have limitations and HFS-defaults for several years, at least on macOS, as the file system matures. Either way, what file system didn't take years to get right? There are so many possible edge cases with file systems that it not only takes a long time to sort them out, but an amazing community and/or luck to reproduce deterministically to fix them.
mcepl 10y ago
File systems take A LONG time to stabilize, and you want them stabilized well, because if there is a bug in httpd, you just restart it, if there is a bug in filesystem you loose your data. See BTRFS. Started in 2007 and it is still not stable enough to be supported in RHEL (and for good reasons). So, of course, Apple engineers are way better than the rest of the world and they have magical pixie dust which makes bugs disappear, so they will fix bugs way faster than anybody else. Not.
zyx321 10y ago
It's good to see Apple catching up, no matter where it's coming from. You mention ZFS, but per-file encryption (EFS) and snapshots (VSS) in particular stood out to me as features NTFS has had for a decade.
leonroy 10y ago
Anyone know who works on APFS? If I were Apple I would have certainly picked up some of the ZFS core team, curious if any of them are currently at Apple. Could speed up their time to market with such seasoned hands on board.
- lapfelix 10y ago
  One of them worked on the 'Be File System'... that's interesting https://en.wikipedia.org/wiki/Dominic_Giampaolo https://en.wikipedia.org/wiki/Dominic_Giampaolo
niutech 10y ago
It seems ZFS was a no-go because of its license. But why does Apple develop its APFS rather than port the open source BTRFS with all its features? NIH syndrome?
- tveita 10y ago
  Probably still because of the license? Btrfs is GPL. It will be interesting to see which license, if any, APFS is released under.

by ahl 10y ago

watersb 10y ago

Yes. I was a heavy user of ZFS on Mac OS X back then. Was on the developer mailing list for that implentation, submitting bugs and talking to Apple developers working like mad to ship it. Then Steve Jobs' buddy Larry bought Sun, and licensing of ZFS became basically impossible to sort out on time. So they dropped it. Was that 2007 or 2009?

ahl 10y ago
The Sun acquisition was announced in 2009 and closed in 2010. It may have been related, but I have my own suspicions about about what caused Apple to jettison their port.
- rafaelferreira 10y ago
  Do tell.
- astrodust 10y ago
  Given the mountain of legal shit Google has been subjected to over Java, the last thing Apple wanted was to have to answer to Larry's lawyers. ZFS, awesome as it is, has been poisoned.
- wmf 10y ago
  It's like no one here remembers the NetApp lawsuit.
rangibaby 10y ago
2009. I remember ZFS was coming in Snow Leopard. Then it wasn't /edit https://web.archive.org/web/20080721031014/http://www.apple.com/server/macosx/snowleopard/ https://web.archive.org/web/20080721031014/http://www.apple....
saithier 10y ago
The thing that killed ZFS on the Mac was the NetApp lawsuit over it against Sun.

jburwell 10y ago

It's impossible to know how long they have been working on it. As I recall, Swift had been in development for 3+ years before it saw the light of day.

gh02t 10y ago
Yeah, I bet it's been in development for a while. People have been seriously bitching about HFS+ for at least a decade, and with good reason. Apple has been pretty much silent about it apart from briefly testing ZFS and I'd wager a guess that they started working on it shortly after they abandoned that, while they continued also bolting more stuff onto HFS+ in the meantime.

mioelnir 10y ago

Between the ZFS-like features and the advertised "novel copy-on-write metadata" scheme, I would not be surprised if it was partially based on DragonFly's HAMMER/HAMMER2 filesystem.

ahl 10y ago
It would be a strange kind of NIH that excluded ZFS but welcomed HAMMER...
- feld 10y ago
  different licensing and HAMMER demands significantly less memory
- AceJohnny2 10y ago
  Licensing.
  - deleted 10y ago
    [deleted]
mindajar 10y ago
If you poke around in the the APFS kernel extension, it's not a very big binary, given the feature set. (It's a 550K extension, compared to the 2.5MB zfs.ko on FreeBSD.) I haven't disassembled it yet, but I'd wager that APFS is layered atop Core Storage btrees/CoW. Since that code's been shipping since 2011, maybe APFS stabilizes faster than a true greenfield filesystem? (That does leave me wondering how interesting an open-source APFS would be without an open-source Core Storage.)
- Freaky 10y ago
  > It's a 550K extension, compared to the 2.5MB zfs.ko on FreeBSD hammer.ko is 494KB in the latest DFBSD, for those wondering the obvious.
Wildgoose 10y ago

azinman2 10y ago

Unless I'm misreading, the page seems to indicate that only external volumes can be formatted with APFS. My guess is that they'll have limitations and HFS-defaults for several years, at least on macOS, as the file system matures. Either way, what file system didn't take years to get right? There are so many possible edge cases with file systems that it not only takes a long time to sort them out, but an amazing community and/or luck to reproduce deterministically to fix them.

mcepl 10y ago

File systems take A LONG time to stabilize, and you want them stabilized well, because if there is a bug in httpd, you just restart it, if there is a bug in filesystem you loose your data. See BTRFS. Started in 2007 and it is still not stable enough to be supported in RHEL (and for good reasons). So, of course, Apple engineers are way better than the rest of the world and they have magical pixie dust which makes bugs disappear, so they will fix bugs way faster than anybody else. Not.

zyx321 10y ago

It's good to see Apple catching up, no matter where it's coming from. You mention ZFS, but per-file encryption (EFS) and snapshots (VSS) in particular stood out to me as features NTFS has had for a decade.

leonroy 10y ago

Anyone know who works on APFS? If I were Apple I would have certainly picked up some of the ZFS core team, curious if any of them are currently at Apple. Could speed up their time to market with such seasoned hands on board.

lapfelix 10y ago
One of them worked on the 'Be File System'... that's interesting https://en.wikipedia.org/wiki/Dominic_Giampaolo https://en.wikipedia.org/wiki/Dominic_Giampaolo

niutech 10y ago

It seems ZFS was a no-go because of its license. But why does Apple develop its APFS rather than port the open source BTRFS with all its features? NIH syndrome?

tveita 10y ago
Probably still because of the license? Btrfs is GPL. It will be interesting to see which license, if any, APFS is released under.