Comments on: Is Apple’s Time Machine Built On Sun’s ZFS? http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/ Data storage info & analysis Wed, 07 Jan 2009 08:20:05 +0000 http://wordpress.org/?v=2.7 hourly 1 By: Petieg http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-75978 Petieg Wed, 06 Jun 2007 18:28:11 +0000 http://storagemojo.com/?p=213#comment-75978 and now it seems that you are right!!! http://www.macrumors.com/2007/06/06/zfs-to-become-default-file-system-in-leopard/ and now it seems that you are right!!! http://www.macrumors.com/2007/06/06/zfs-to-become-default-file-system-in-leopard/

]]> By: jimy http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-15560 jimy Wed, 10 Jan 2007 21:54:28 +0000 http://storagemojo.com/?p=213#comment-15560 afraid its not ZFS filesystem for time machine. Time machine works in developer builds on a HFS+ Drive. Well, HFS+ drive with 2 partitions in my case. But ZFS file support is included in the latest build. You can select it from a drop down list in Disk Utility, though currently it seems to be inactive. Bit of a dead link. It seems though apple have included hooks for support of ZFS for 10.5 though. If you google 10.5 Leopard Build 9A321, you can find screenshots showing ZFS in disk utility. afraid its not ZFS filesystem for time machine. Time machine works in developer builds on a HFS+ Drive. Well, HFS+ drive with 2 partitions in my case. But ZFS file support is included in the latest build. You can select it from a drop down list in Disk Utility, though currently it seems to be inactive. Bit of a dead link. It seems though apple have included hooks for support of ZFS for 10.5 though. If you google 10.5 Leopard Build 9A321, you can find screenshots showing ZFS in disk utility.

]]> By: se http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-12413 se Wed, 20 Dec 2006 10:45:45 +0000 http://storagemojo.com/?p=213#comment-12413 well it seems he definitely WAS right afterall... and the Apple guy a hoax ;) well it seems he definitely WAS right afterall…

and the Apple guy a hoax ;)

]]> By: Chris http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-5265 Chris Mon, 14 Aug 2006 01:57:04 +0000 http://storagemojo.com/?p=213#comment-5265 I would like to point out that this could only currently be a hack on the back end while Apple gets ZFS ready for next spring when Leopard is supposed to ship. It looks too much like the front end was made for ZFS snapshots. I would like to point out that this could only currently be a hack on the back end while Apple gets ZFS ready for next spring when Leopard is supposed to ship. It looks too much like the front end was made for ZFS snapshots.

]]> By: David Magda http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-5107 David Magda Wed, 09 Aug 2006 22:42:37 +0000 http://storagemojo.com/?p=213#comment-5107 Another issue with ZFS is that it is currently case-sensitive. While this isn't necessarily a show-stopper (OS X supports case-sensitive UFS), some developers--and a good portion of users--are not expecting, it so bugs may show up in odd places. Note Mac OS has used insensitive file systems since the beginning (HFS, HFS+). The FreeBSD people have gotten a preliminary configuration of DTrace up in the 7.x development branch, but no one has gotten ZFS set up yet (on any OS; though I think there's a port to FUSE). So it seems that DTrace is the easier of the two to port (for a sample size of two projects so far). And while Unix does have a layer to abstract file systems, the architecture of ZFS is quite different than anything else before it, so just plugging it in isn't easy. With Unix's VFS you usually have a block device (e.g., disk) to deal with, so the VFS layer was built with that assumption. Most current volume management (e.g. Linux's LVM, Veritas) actually present themselves as a block device to the file system. So you would take a couple of disks, bring them together using LVM, and present them as a 'disk' to the file system you wanted to use (ext3, vxfs, Reiser, HFS, UFS). What ZFS does is replace both layers (what LVM and ext3 do), and roll them up into one architecture. Most file systems also assume a fixed size of writing blocks, while ZFS can have dynamic blocks (512B to 128KB), so that may expose assumptions in certain code (it was brought up as a concern by the DragonFly BSD developers). P.S. Is it possible to have a 'preview comment' button? Proof reading stuff in this text area isn't the greatest, and I like personally like to see how things are going to be rendered before submitted as well. Another issue with ZFS is that it is currently case-sensitive. While this isn’t necessarily a show-stopper (OS X supports case-sensitive UFS), some developers–and a good portion of users–are not expecting, it so bugs may show up in odd places. Note Mac OS has used insensitive file systems since the beginning (HFS, HFS+).

The FreeBSD people have gotten a preliminary configuration of DTrace up in the 7.x development branch, but no one has gotten ZFS set up yet (on any OS; though I think there’s a port to FUSE). So it seems that DTrace is the easier of the two to port (for a sample size of two projects so far).

And while Unix does have a layer to abstract file systems, the architecture of ZFS is quite different than anything else before it, so just plugging it in isn’t easy. With Unix’s VFS you usually have a block device (e.g., disk) to deal with, so the VFS layer was built with that assumption. Most current volume management (e.g. Linux’s LVM, Veritas) actually present themselves as a block device to the file system.

So you would take a couple of disks, bring them together using LVM, and present them as a ‘disk’ to the file system you wanted to use (ext3, vxfs, Reiser, HFS, UFS). What ZFS does is replace both layers (what LVM and ext3 do), and roll them up into one architecture. Most file systems also assume a fixed size of writing blocks, while ZFS can have dynamic blocks (512B to 128KB), so that may expose assumptions in certain code (it was brought up as a concern by the DragonFly BSD developers).

P.S. Is it possible to have a ‘preview comment’ button? Proof reading stuff in this text area isn’t the greatest, and I like personally like to see how things are going to be rendered before submitted as well.

]]> By: Robin Harris http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-5104 Robin Harris Wed, 09 Aug 2006 21:47:19 +0000 http://storagemojo.com/?p=213#comment-5104 You have a point - and Apple's use of HFS+ now doesn't preclude moving to something better later. Sun's DTrace was released in late January 2005 under an open-source license. OS X support for DTrace was just announced this week. ZFS was released in mid-November, 2005. If Apple were porting it, would it take 18 months? I have no idea how the complexity of integrating DTrace into the Darwin kernal compares to porting a file system like ZFS. I thought Unix was designed to allow file systems to be plugged in, yet there could be lots of dependencies in Aqua or ??? that I don't grok. Would any of my plugged in readers like to comment? You have a point - and Apple’s use of HFS+ now doesn’t preclude moving to something better later.

Sun’s DTrace was released in late January 2005 under an open-source license. OS X support for DTrace was just announced this week. ZFS was released in mid-November, 2005. If Apple were porting it, would it take 18 months?

I have no idea how the complexity of integrating DTrace into the Darwin kernal compares to porting a file system like ZFS. I thought Unix was designed to allow file systems to be plugged in, yet there could be lots of dependencies in Aqua or ??? that I don’t grok.

Would any of my plugged in readers like to comment?

]]> By: Codeless http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-5100 Codeless Wed, 09 Aug 2006 19:51:02 +0000 http://storagemojo.com/?p=213#comment-5100 There was no realistic chance of getting ZFS this quickly. Somebody in Apple expresses interest in a mailing list and then it gets ported and shipped in just a few months? No way. A major piece of functionality like that demands a long period of testing before it goes anywhere near users, let alone being trumpeted as a flagship product feature. There was no realistic chance of getting ZFS this quickly. Somebody in Apple expresses interest in a mailing list and then it gets ported and shipped in just a few months? No way. A major piece of functionality like that demands a long period of testing before it goes anywhere near users, let alone being trumpeted as a flagship product feature.

]]> By: Spoiler http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-5086 Spoiler Wed, 09 Aug 2006 14:30:18 +0000 http://storagemojo.com/?p=213#comment-5086 Sorry, guys, but no. It works just like Backup 3. It creates a sparse image and then copies the files onto it in stages. It's not ZFS or using any special filesystem tricks; it's just copying files incrementally on a schedule. ZFS is not in the Leopard discussed at WWDC in any capacity. Sorry, guys, but no. It works just like Backup 3. It creates a sparse image and then copies the files onto it in stages. It’s not ZFS or using any special filesystem tricks; it’s just copying files incrementally on a schedule.

ZFS is not in the Leopard discussed at WWDC in any capacity.

]]> By: Robin Harris http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-5080 Robin Harris Wed, 09 Aug 2006 13:50:42 +0000 http://storagemojo.com/?p=213#comment-5080 Gosh, I hate it when I'm wrong. But I'm not (yet) convinced I am. As Adam Leventhal of the ZFS team notes - thanks for the link David - Time Machine would have a ". . . sort of dubious back end . . . ." From a data integrity perspective, HFS+ isn't that good. I've been using it for years, and without regular attention from Disk Warrior - not yet available for Intel-based Macs - it goes south slowly and surely, for all the reasons that ZFS was engineered to avoid. Yet I did miss Apple's line: "Time Machine will back up every night at midnight, unless you select a different time from this menu." That is NOT ZFS-like behavior. It also invites all the problems that people already have with existing backup solutions, such as the "my Mac was asleep so it didn't get backed up" issue. So, *sob,* I could be wrong. Yet if Apple bases Time Machine on journaled HFS+, they are exposing themselves to great customer unhappiness when it doesn't work as advertised after a year. And they certainly aren't going to have a competitive advantage over NTFS, with or without WinFS. Gosh, I hate it when I’m wrong. But I’m not (yet) convinced I am. As Adam Leventhal of the ZFS team notes - thanks for the link David - Time Machine would have a “. . . sort of dubious back end . . . .”

From a data integrity perspective, HFS+ isn’t that good. I’ve been using it for years, and without regular attention from Disk Warrior - not yet available for Intel-based Macs - it goes south slowly and surely, for all the reasons that ZFS was engineered to avoid.

Yet I did miss Apple’s line: “Time Machine will back up every night at midnight, unless you select a different time from this menu.” That is NOT ZFS-like behavior.

It also invites all the problems that people already have with existing backup solutions, such as the “my Mac was asleep so it didn’t get backed up” issue.

So, *sob,* I could be wrong. Yet if Apple bases Time Machine on journaled HFS+, they are exposing themselves to great customer unhappiness when it doesn’t work as advertised after a year. And they certainly aren’t going to have a competitive advantage over NTFS, with or without WinFS.

]]> By: David Magda http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-5074 David Magda Wed, 09 Aug 2006 11:42:53 +0000 http://storagemojo.com/?p=213#comment-5074 According to a message on the zfs-discuss list, it seems that they may not be doing it: http://mail.opensolaris.org/pipermail/zfs-discuss/2006-August/004250.html No way to be 100% sure until you get a copy of Leopard though. According to a message on the zfs-discuss list, it seems that they may not be doing it:

http://mail.opensolaris.org/pipermail/zfs-discuss/2006-August/004250.html

No way to be 100% sure until you get a copy of Leopard though.

]]> By: John C. Randolph http://storagemojo.com/2006/08/08/is-apples-time-machine-built-on-suns-zfs/comment-page-1/#comment-5066 John C. Randolph Wed, 09 Aug 2006 07:26:50 +0000 http://storagemojo.com/?p=213#comment-5066 Sorry, but you're  wrong.  Turns out that it's done with HFS+ journaling. -jcr Sorry, but you’re  wrong.  Turns out that it’s done with HFS+ journaling.

-jcr

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