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Tru64 Unix Advanced File System (AdvFS) Now GPL
melios writes "In a move that could help boost the scalability of Linux for grids and other advanced 64-bit multiprocessor applications, HP has released its Tru64 Unix Advanced File System (AdvFS) source code to the open source community. Source code, design documentation, and test suites for AdvFS are available on SourceForge."
I didn't know any of the details of what AdvFS was, so here is what Wikipedia has: http://en.wikipedia.org/wiki/AdvFS
AdvFS is comparable in features to ZFS - it has snapshotting, intelligent striping and mirroring, dynamic resizing, etc.
In short, there's no comparable production filesystem in Linux right now. There's Btrfs from Oracle, but it's in deep alpha.
Comparison Of File Systems
Although its missing from some of the charts...
AdvFS
And that page is rather limited in information.
No, it can't. XFS has not the concept of "storage pool" that ZFS and AdvFS have. It doesn't have ZFS/AdvFS-style snapshots. XFS is also a journaling filesystem, unlike ZFS (AdvFS however is a journaled filesystem - and even then, the journaling modes of advfs allow to configure a much better data integrity than ZFS)
It doesn't have the Merkle tree and the associated error-detection properties of ZFS though.
Also, AdvFS (or PolyFS, as I could swear it was called in the beginning - though Google can't seem to any record of it) had a pretty bad reliability record in its earlier days, at least bad enough that its unreliability still was mentioned in DEC Open Systems Support when I visited there in 2000.. (by which stage Tru64 clearly was on life-support). ;)
I use Friend/Foe + mod-point modifiers as a karma/reputation system.
This was the filesystem that HP tried to port to HPUX and failed. They licensed Veritas instead.
I figured that the multithreading that I'd always heard worked so well in AdvFS/Tru64 was hard to port to the non-multithreaded HPUX kernel.
http://news.zdnet.co.uk/hardware/0,1000000091,39175690,00.htm
"It had initially planned to complete the migration of the TruCluster/AdvFS feature from Tru64 Unix to HP-UX 11i v3 in the middle of 2006."
http://forums12.itrc.hp.com/service/forums/questionanswer.do?admit=109447627+1214253121145+28353475&threadId=754760
"No TruCluster or AdvFS for HP-UX after all"
No. XFS is a multimedia-oriented filesystem, it was designed to support multithreaded streaming with guaranteed access times. It works well for these use-cases.
But it doesn't work well for a lot of other use-cases, though. Hence, the current development of Btrfs.
Is there some reason to pick this file system over any of the other 100 file systems you can get for Linux?
AdvFS is a clustered FS.
"I don't know, therefore Aliens" Wafflebox1
To answer your question, yes the utilities are user GPL-license.
New things are always on the horizon
As for "too much choice", you may prefer to solve every problem with a hammer but I prefer a toolbox.
This was the filesystem that HP tried to port to HPUX and failed. They licensed Veritas instead.
http://news.zdnet.co.uk/hardware/0,1000000091,39175690,00.htm "It had initially planned to complete the migration of the TruCluster/AdvFS feature from Tru64 Unix to HP-UX 11i v3 in the middle of 2006."
http://forums12.itrc.hp.com/service/forums/questionanswer.do?admit=109447627+1214253121145+28353475&threadId=754760 "No TruCluster or AdvFS for HP-UX after all"
It probably would have made the release too, except that it got canned after it was working.
It wasn't that HP failed to port ADVfs and trucluster to HPUX -- it was that they decided to stop it in favor of the other solution for arguably political and financial reasons. The people at HP in California were more than happy for the DEC people in New Hampshire to go away, even at the cost of licensing something that was no better than what they already owned outright, but would need to fund support for.
One wonders why they have bothered with this release at this point.
-dB
"It if was easy to do, we'd find someone cheaper than you to do it."
And that's why SuSE sucks, it still defaults to reiser.
It hasn't since about 2006 in the OpenSuSE versions. Their timing kind of sucked though, since the change was just after the stable Enterprise versions shipped.Forgot to mention: 1) VMS is also outstanding. A VMS cluster apparently holds the record for "uptime"; over 10 years: http://www.openvms.org/stories.php?story=06/01/08/4531954 2) Did I mention Carly Fiorina sucks ass
It doesn't have the Merkle tree and the associated error-detection properties of ZFS though.
Also, AdvFS (or PolyFS, as I could swear it was called in the beginning - though Google can't seem to any record of it) had a pretty bad reliability record in its earlier days, at least bad enough that its unreliability still was mentioned in DEC Open Systems Support when I visited there in 2000.. (by which stage Tru64 clearly was on life-support). ;)
It was pretty flakey around Tru64 v4, but got a major re-write for Tru64 v5 which cleared up the problems and made it very stable after that. Today, it's the most stable filesystem I've ever used. And you're right about the Poly stuff. There was a marketing drive which fortunately didn't last very long where they tried to brand it as the Polyserve filesystem, then it got changed. Even Polyserve was an improvement on its birth name, the MegaSafe Filesystem. You can still see remnants of that in the Tru64 kernel config file: its the options MSFS line that triggers inclusion of AdvFS into the kernel. The word MegaSafe also crops up all over the source tree too. Go take a lookActually, Apple isn't exactly moving from Old FS (HFS+) to New FS (UFS, née FFS) any time soon. HFS+ is basically required for the boot volume, and HFS+ has a number of features that don't exist in UFS (ACLs, file creation dates, extents, journaling, file type and creator codes, archive timestamps, etc.). That said, HFS+ certainly sucks for a number of reasons, but UFS is no replacement candidate. ZFS has a future with the Xserve and other server uses, but whether ZFS will ever be used on the Apple desktop remains to be seen; current suspicion is that it probably won't since ZFS isn't bootable on Sun machines yet.
"He can't change the kernel to be GPLv3 compatible after the fact."
Yes he can. He even said how (while I can't find the reference on Google, lame me). Basically, he would do a public announcement: Hey, folks, I'll go GPLv3 in six months; whoever that have something to say, do so or be silent for ever. By the way, that's how he went from GPLv1 to GPLv2 quite some years ago.
1) FAT is a very simple file system and the Linux implementation of NTFS is even less complete than ext2 is on Windows.
2) Linux users have a larger need/want to run FAT/NTFS than Windows users need/want to run ext2. Necessity, invention, etc.
3) Obviously, Windows is case retentive not case sensitive. As I said, Windows isn't Unix so Unix file systems aren't going to port well.
If anything, NTFS would port easier to Linux because NTFS is a much more feature rich file system than most *nix filesystems.
Opportunity knocks. Karma hunts you down.
Which would be why the subject references "Digital UNIX", which was the name used by DEC after they gave up on OSF/1. Tru64 was Compaq's name for it, because they really hated words that were spelled correctly.
Of course if you know enough to nit-pick that then you would also know about what happened to it after the HP-Compaq merger and how the last surviving Digital engineers tried to weld useful features like AdvFS and TruCluster onto HP-UX only to have their projects canceled in favour of inferior and more expensive Carly-approved products.
So I won't explain that, given the lineage of the code, it's probably the stuff that was ported to HP-UX.
I remember reading responses by kernel devs saying they would not put ZFS into the kernel, regardless of license. IIRC, it was because it violated in so many spectacular ways the concept of layering.
Yes, which is how it is able to do the amazing things that it does. Some of the stuff ZFS does -- and only ZFS does -- is because the storage management and filesystem are merged.
The people who bash ZFS haven't used it, haven't researched it, or both.