NAME

       bup-gc - remove unreferenced, unneeded data (CAUTION: EXPERIMENTAL)

SYNOPSIS

       bup gc [-#|--verbose] <branch|save...>

DESCRIPTION

       bup gc removes (permanently deletes) unreachable data from the repository, data that isn't
       referred to directly or indirectly by the current set of branches (backup sets) and  tags.
       But  bear  in  mind  that  given  deduplication,  deleting  a save and running the garbage
       collector might or might not actually delete anything (or reclaim any space).

       With the current, proababilistic implementation, some fraction of the unreachable data may
       be  retained.  In exchange, the garbage collection should require much less RAM than might
       by some more precise approaches.

       Typically, the garbage collector would be invoked after some set of invocations of bup rm.

       WARNING: This is one of the few bup commands that modifies your archive  in  intentionally
       destructive  ways.   Though if an attempt to join or restore the data you still care about
       after a gc succeeds, that's a fairly encouraging sign that the commands worked  correctly.
       (The  t/compare-trees  command  in  the  source tree can be used to help test before/after
       results.)

OPTIONS

       --threshold=N
              only rewrite a packfile if it's over N percent garbage; otherwise leave  it  alone.
              The default threshold is 10%.

       -v, --verbose
              increase  verbosity  (can  be  used more than once).  With one -v, bup prints every
              directory name as it gets backed up.  With two -v, it also prints every filename.

       -#, --compress=#
              set the compression level to # (a value from 0-9, where 9 is the highest and  0  is
              no compression).  The default is 1 (fast, loose compression).

EXAMPLES

              # Remove all saves of "home" and most of the otherwise unreferenced data.
              $ bup rm home
              $ bup gc

SEE ALSO

       bup-rm(1) and bup-fsck(1)

BUP

       Part of the bup(1) suite.

AUTHORS

       Rob Browning <rlb@defaultvalue.org>.