5 ms·

The Translucent File Service (1988) [pdf]

27 points by jxub 8y ago

mpweiher 8y ago
Neat! I didn't know the copy-on-write semantics for filesystems went back that far, the first I knew about was UnionFS[1][2], which features the same semantics in a larger package. [1] http://unionfs.filesystems.org http://unionfs.filesystems.org [2] https://en.wikipedia.org/wiki/UnionFS https://en.wikipedia.org/wiki/UnionFS
- Fnoord 8y ago
  > I didn't know the copy-on-write semantics for filesystems went back that far WAFL [1] from NetApp was/is widely in use, utilising CoW, and possibly older than this paper (wasn't able to verify but I know its from '90s at least). This paper might've been interesting for the legal dispute between Sun and NetApp. Got settled with Oracle in 2010 though. [1] https://en.wikipedia.org/wiki/Write_Anywhere_File_Layout https://en.wikipedia.org/wiki/Write_Anywhere_File_Layout
  - close04 8y ago
    TFS introduced copy-on-write in 1986 (with SunOS 3). This is probably the first such implementation. Not sure if there was anything comparable before that, meeting the same definition of layered and copy-on-write. WAFL came a few years later - in development in the early '90s, reached production in 1994.
    - Fnoord 8y ago
      My bad, I read through the document but I misread it as 1998.
  - cryptonector 8y ago
    The 4.4BSD log-structured filesystem was the first CoW FS I'm aware of. The ideas go back earlier still to the DB world. There is a lot of prior art in this space.
- invalidusernam3 8y ago
  For others like me who aren't sure what copy-on-write is: https://stackoverflow.com/questions/628938/what-is-copy-on-write https://stackoverflow.com/questions/628938/what-is-copy-on-w...
- cryptonector 8y ago
  The BSD 4.4 log-structured file system is the earliest CoW FS that I know of, though the ideas really go back earlier to the database world. (There's a tremendous amount of duality between databases and filesystems, so much so that it's pretty shocking that they haven't quite merged. WinFS should not have failed.) I think of ZFS as a direct descendant of the 4.4BSD LFS, though I don't know that it is so -- in fact, I suspect Bonwick et. al. did not take inspiration from 4.4BSD LFS, but came up with a filesystem that looks inspired by it.
toddh 8y ago
NSE was an awesome development environment when it worked. Unfortunately, it often became corrupted and suffered a lot of down time. Just a touch too much cleverness for the systems at the time.
lgats 8y ago
https://exif.tools/http://mcvoy.com/lm/papers/SunOS.tfs.pdf https://exif.tools/http://mcvoy.com/lm/papers/SunOS.tfs.pdf

27 points by jxub 8y ago

Neat! I didn't know the copy-on-write semantics for filesystems went back that far, the first I knew about was UnionFS[1][2], which features the same semantics in a larger package. [1] http://unionfs.filesystems.org http://unionfs.filesystems.org [2] https://en.wikipedia.org/wiki/UnionFS https://en.wikipedia.org/wiki/UnionFS

Fnoord 8y ago
> I didn't know the copy-on-write semantics for filesystems went back that far WAFL [1] from NetApp was/is widely in use, utilising CoW, and possibly older than this paper (wasn't able to verify but I know its from '90s at least). This paper might've been interesting for the legal dispute between Sun and NetApp. Got settled with Oracle in 2010 though. [1] https://en.wikipedia.org/wiki/Write_Anywhere_File_Layout https://en.wikipedia.org/wiki/Write_Anywhere_File_Layout
- close04 8y ago
  TFS introduced copy-on-write in 1986 (with SunOS 3). This is probably the first such implementation. Not sure if there was anything comparable before that, meeting the same definition of layered and copy-on-write. WAFL came a few years later - in development in the early '90s, reached production in 1994.
  - Fnoord 8y ago
    My bad, I read through the document but I misread it as 1998.
- cryptonector 8y ago
  The 4.4BSD log-structured filesystem was the first CoW FS I'm aware of. The ideas go back earlier still to the DB world. There is a lot of prior art in this space.
invalidusernam3 8y ago
For others like me who aren't sure what copy-on-write is: https://stackoverflow.com/questions/628938/what-is-copy-on-write https://stackoverflow.com/questions/628938/what-is-copy-on-w...
cryptonector 8y ago
The BSD 4.4 log-structured file system is the earliest CoW FS that I know of, though the ideas really go back earlier to the database world. (There's a tremendous amount of duality between databases and filesystems, so much so that it's pretty shocking that they haven't quite merged. WinFS should not have failed.) I think of ZFS as a direct descendant of the 4.4BSD LFS, though I don't know that it is so -- in fact, I suspect Bonwick et. al. did not take inspiration from 4.4BSD LFS, but came up with a filesystem that looks inspired by it.

toddh 8y ago

NSE was an awesome development environment when it worked. Unfortunately, it often became corrupted and suffered a lot of down time. Just a touch too much cleverness for the systems at the time.

lgats 8y ago

https://exif.tools/http://mcvoy.com/lm/papers/SunOS.tfs.pdf https://exif.tools/http://mcvoy.com/lm/papers/SunOS.tfs.pdf