[OpenIndiana-discuss] leaked space?

[Jim Klimov]

On 2013-07-22 19:19, Brett Dikeman wrote:
> What exactly does this mean? What is "leaked space"? Is it repaired by
> virtue of zdb walking the filesystem, etc?

No, zdb is a read-only investigation tool that runs in userspace and
accesses the pool devices directly (bypassing ZFS kernel modules).
It is largely based on the same ZFS code in the sources, so in terms
of feature compatibility it should be consistent with kernel ZFS on
the same release of an OS.

Leaked space (and oppositely double allocations) is a discrepancy
between an allocation map determined from walking whole metadata
tree, and the free-space maps located on disks in the process.
If you ZDB-walk a live pool, its contents change with each TXG, so
these discrepancies are expected and don't mean anything really.
If you see this on an exported pool, there may be a problem that
can be discussed and researched further.

HTH,
//Jim Klimov