[OmniOS-discuss] Clues for tracking down a drastic ZFS fs space difference?

[Paul B. Henson]

> From: Chris Siebenmann
> Sent: Wednesday, April 29, 2015 12:21 PM
>
> ZFS level; as you can see, it's added 22 GB of ZFS usage in less than
> a month while losing 5 GB at the user level.

There was a thread late last year on the developer list that described
similar symptoms:

http://lists.open-zfs.org/pipermail/developer/2014-October/000887.html

Have you by any chance done zfs recv into this filesystem, and then further
have the async_destroy feature enabled? If so, you could possibly be hitting
this issue. zdb -bb on the pool would show an increasing amount of deferred
frees over time.

I see from a more recent message you're running a rather ancient kernel, so
you might not even have this feature. But it feels like we are in the throw
darts at the wall stage of problem solving ATM, so here you go :), good
luck.