Changing the DEFAULT_SIZE_CUTOFF

g2p / bedup

Btrfs deduplication

http://pypi.python.org/pypi/bedup

GNU General Public License v2.0

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Changing the DEFAULT_SIZE_CUTOFF #28

Closed sdteffen closed 11 years ago

sdteffen commented 11 years ago

It would be great if some documentation could be added regarding the size cutoff:

Is there a minimum size beyond which it will not make sense to lower the cutoff value (due to metadata overhead) ?
Is it possible to change the cutoff value for a volume that has already been deduped? Which steps have to be taken in that case?
Would it make sense to expose the cutoff value as a commandline parameter?

g2p commented 11 years ago

It's not directly documented in the README, but bedup dedup --help answers the last two questions. Metadata space overhead puts an absolute floor around the filesystem leaf size, but the io overhead of scanning small files vs the dedup opportunities just depends on what kind of data your filesystem contains.