Re: Hammer pruning and pfs

[Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx>]

:Hi,
:
:it's unclear to me whether pruning works locally to a PFS or not.
:
:Say I have a snapshots directory with links to PFS#1, e.g.
:
:   /pfs1/snapshots
:   snap1 -> /pfs1/@0x....
:   snap2 -> /pfs1/@0x....
:
:and I do a
:
:   hammer prune /pfs1/snapshots
:
:will it just prune the PFS#1 accoring to the softlinks, or
:will it prune the whole Hammer filesystem using the softlinks.
:
:My understanding is that each PFS can be pruned separatly (otherwise 
:mirroring using per-mirror retention policies will not work).
:But then, if one has multiple PFS, one has to maintain multiple
:snapshots for each PFS, even if the transaction id of the snapshot
:is global to the whole Hammer filesystem.
:
:Regards,
:
:   Michael

    Yes.  The actual pruning and reblocking ioctl's include parameters
    for specifying the PFS.

    The hammer prune and reblock commands actually test whether you
    are specifying a PFS softlink and figure out which PFS you are
    referencing.  Theoretically just that PFS should be reblocked
    or pruned.

					-Matt
					Matthew Dillon 
					<dillon@backplane.com>