ZFS features (SPA_VERSION successor)

[Martin Matuska]

Hi folks,

last week Illumos has introduced a new concept called "ZFS features", a
version-independent successor to SPA_VERSION, together with the first
"feature" - async destroy.
It is a huge commit and will take some time to implement (there is quite
detailed documentation and manpages inside).

As to the text in the issue 2619, the feature flags are based on a
proposal to the ZFS working group:
http://lists.freebsd.org/pipermail/freebsd-fs/2011-May/011568.html

Maybe some of FreeBSD-related ZFS development could take advantage of
this, when ported.

References:
https://hg.openindiana.org/upstream/illumos/illumos-gate/rev/2889e2596bd6
https://hg.openindiana.org/upstream/illumos/illumos-gate/rev/1949b688d5fb
https://www.illumos.org/issues/2619
https://www.illumos.org/issues/2747

Cheers,
mm

-- 
Martin Matuska
FreeBSD committer
http://blog.vx.sk