ZFS-FUSE

ZFS is the most advanced file system ever invented. The ZFS-FUSE project makes it possible to create, mount, use and manage ZFS file systems under Linux, bringing the uncontested reliability and large feature set of ZFS to the Linux world.

What ZFS offers to you

ZFS has many features for all kinds of users - from the simple end-user to the biggest enterprise systems:

* Provable integrity - it checksums all data (and meta-data), which makes it possible to detect hardware errors (hard disk corruption, flaky IDE cables..). Read how ZFS helped to detect a faulty power supply after only two hours of usage, which was previously silently corrupting data for almost a year!
* Atomic updates - means that the on-disk state is consistent at all times, there's no need to perform a lengthy filesystem check after forced reboots/power failures.
* Instantaneous snapshots and clones - it makes it possible to have hourly, daily and weekly backups efficiently, as well as experiment with new system configurations without any risks.
* Built-in (optional) compression
* High scalability
* Pooled storage model - creating filesystems is as easy as creating a new directory. You can efficiently have thousands of filesystems, each with it's own quotas and reservations, and different properties (compression algorithm, checksum algorithm, etc..).
* Built-in stripes (RAID-0), mirrors (RAID-1) and RAID-Z (it's like software RAID-5, but more efficient due to ZFS's copy-on-write transactional model).
* Among others (variable sector sizes, adaptive endianness, ...)

What is new in this release:

• changed the fuse subtype to zfs-fuse This affects the contents of mtab, so everybody with scripts depending on that, please update accordingly!
• pool version 26 (Emmanuel Anne)
• consequently, all Sun's bug fixes; see changelog and upstream. This includes work on Sun BUG 6948890 (snapshot deletion can induce pathologically long spa_sync() times) which became something of a FAQ on the list. Note that datasets removals can still take a long time, especially with dedup enabled*
• robust handling of rollback even when using cache (http://zfs-fuse.net/issues/65); this had been a 'high profile' issue reported on the 0.6.9 release with a workaround delivered in the maintenance version. The workaround however carried a performance penalty for the whole of zfs-fuse (basically killing page caching for zfs-fuse). The new solution is still not ideal, but at least only incurs a penalty when and only when a rollback is performed, this time by dropping all the kernel filesystem caches. We'd much rather have remounted the related filesystem(s) but this cannot always be done, and there is no way to find out whether it did work... We value data integrity above performance in this kind of situation.
• improved init scripts Thanks to all packagers/contributors. There is an upstart script too
• bash completion Contributed by Aneurin Price
• mount filesystems with ACLs (patch by Eric Astor, http://zfs-fuse.net/issues/71). Although I'm not to sure whether the ACLs are (properly) handled, at least zfs-fuse will not abort when a file is used that has ACLs set. Eric Astor did some nice wizardry mapping ids here and there, we'd like feedback from other users that have ACLs?
• Made zpool export and destroy succeed a lot more often (there is a timing issue with fuse umounts and ZFS dataset holds; although we now wait a while before deciding that an export (e.g.) fails, there are still conditions in which you could need to try again. Please let us know if you encounter such a situation, we'd like to get to the root cause here
• Prevent crash on 'zfs get all' with bind mounts
• Fixed local send/receive with deduped streams due to bidirectional pipes missing on linux
• Parsing of zfsrc now robust (several issues)
• new --enable-xattr flag for zfs-fuse daemon. Using xattrs significantly slows down zfs-fuse, but if your application depends on it, now you can enable them. Unfortunately, there is no way to enable/disable this per filesystem (yet).

What is new in version 0.6.9:

• pool version 23
• this includes full Dedup support. The major upstream annoyances have been patched by SUN; Still beware of the Dedup FAQ
• non blocking zfs send/recv (enable local piping e.g.)
• really this is due to an all-new multithreaded dispatch of ioctls
• zpool split
• to boldly split your infinitives and ... mirrors ! No more detach and force import, just 'zpool split pool newpool'
• sharenfs support (with nfs-kernel-server)
• see links below for details on configuration
• fix for 'dataset busy' on export
• kstat interface
• libumem merged from libumem upstream source
• PowerPC support! (tested on Debian PPC)
• Autoreplace (Hot Spares!) support (replaced Solaris'es SMF features with a configurable script)
• you can configure a script in /etc/zfs/zfs_pool_alert to handle vdev failures. If your system has perl, you can use the contributed script
• Configurable stack size limits (by popular demand)
• Dynamically raise kernel mmaps limit for daemon proces
• Experimental waf build support (SCons is still the main mechanism)
• Many many upstream features and fixes merged from onnv-gate
• Primitive autoexpand support
• It doesn't really use the autoexpand property like in Solaris. "zpool online" can be used to trigger autoexpand. According to Emmanuel a simple mount should even do the trick. Beware of resizing physical volumes/partitions that back your pool's vdevs though, in case you might need to reattach devices of smaller size (in case of mirrors/raidz this won't work if the existing vdevs are larger).
• A bash-completion script in contrib (deploy in /etc/bash_completion.d/)

What is new in version 0.6.0:

• Updates:
• Updated ZFS code to pool version 16 (OpenGrok repository 2009-06-03)
• Upgraded to FUSE API version 26.
• Enhancements:
• Display more informative error messages when the FUSE module is not loaded or when zdb is used while zfs-fuse is not running.
• Included several command-line tunables. These let you control caching and mount opts.
• We ship initscripts now. These are configurable.
• Included distribution source maker.
• Bug fixes:
• Fixed regression where ZFS pools would disappear when rebooting or restarting zfs-fuse.
• Fixed compilation error when compiling under Fedora 9 (reported by Uwe Kubosch).
• Fixed minor possibility of write reordering happen during txg sync on SCSI devices.
• Fixed compilation problem under openSUSE 11.0 (Andy Yelland).
• Fixed umount datasets with spaces problem.
• Fixed disappearing datasets bug.
• Conformance with POSIX according to the NTFS-3G tests.
• Reduced memory consumption.

Requirements:

• Filesystem in Userspace