markfasheh / duperemove

Tools for deduping file systems
GNU General Public License v2.0
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Add FAQ "I got two identical files, why are they not deduped" #218

Closed axkibe closed 4 years ago

axkibe commented 5 years ago

Answer: Because they are fragmented differently. On XFS you can try running "xfs_fsr" to defragment them before and thus the extents become duplicates. For BTRFS I don't know.

Ferroin commented 5 years ago

Equivalent on BTRFS would be running btrfs filesystem defrag on each of the individual files.

HaleTom commented 5 years ago

It would be great if this could be done within duperemove (perhaps if enabled by an option).

Am I right in thinking that there's no way of defraging files which have a dupe in a btrfs RO snapshot?

KyleSanderson commented 5 years ago

Indeed, this would be incredibly useful.

lorddoskias commented 4 years ago

I've added this to the FAQ in pull req #235 . Is it clear enough ?

brunoais commented 4 years ago

@lorddoskias I'd add that it is out of duperemove's control

lorddoskias commented 4 years ago

@lorddoskias I'd add that it is out of duperemove's control

The thing is it's not entirely outside of duperemove control. I.e that's the way the current implementation works so it could be re-engineered to work with some other way which would handle this case. I guess I should state that this might change sometimes in the future.

brunoais commented 4 years ago

That works too, IMO.

lorddoskias commented 4 years ago

FAQ entry has been added.