Does it work…?

[grinapo]

Uh I hate it because I find it unlikely but... I tried to see what dedup does and it did nothing.

• Linux 3.13-1-amd64 #1 SMP Debian 3.13.4-1 (2014-02-22) x86_64 GNU/Linux
• I have a 100GB btrfs fs with 80GB+ files.
• btrfs fi df /mnt/btrfs
• cd tmp/ ; for i in {1..5}; do cp -av ../misc/stuff dupe${i}; done
• btrfs fi df /mnt/btrfs
• bedup dedup
• btrfs fi df /mnt/btrfs

The stuff is around 1GB, and in step 4 it's correctly allocated: Data, single: total=94.00GiB, used=93.55GiB System, DUP: total=8.00MiB, used=20.00KiB System, single: total=4.00MiB, used=0.00 Metadata, DUP: total=1.38GiB, used=205.36MiB

The problem is that: 1) dedup lists 8-10 files as "deduplicating", there should've been 500+ 2) in step6 the status is exactly the same, give or take a few hundred MBs

There should've been 4GB free'd. Or?

[g2p]

If bedup lists just 8-10 file groups, it's either due to the size cutoff or to data that wasn't flushed to disk at the time you ran the deduplication (by default, btrfs can wait up to 30s before flushing). Try these two flags: --flush and --size-cutoff. Also, if fi df doesn't seem to give the right results, you can compare two files with filefrag -v and check that their extents are the same after deduplication.

[ivanbaldo]

This report should be closed, thanks.

[g2p]

Indeed. Closed, works for me.