markfasheh / duperemove

Tools for deduping file systems
GNU General Public License v2.0
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feature request: speed improvment by skipping identical extends #157

Closed Floyddotnet closed 7 years ago

Floyddotnet commented 8 years ago

To simple steps to reproduce:

#Example 1:
dd if=/dev/urandom bs=1024 count=1GB of=/btrfs/dummy
cp dummy /btrfs/dummy.1
cp dummy /btrfs/dummy.2
cp dummy /btrfs/dummy.3
#Example 2:
dd if=/dev/urandom bs=1024 count=1GB of=/btrfs/dummy
btrfs subvolume create /btrfs/sub1
btrfs subvolume create /btrfs/sub2
btrfs subvolume create /btrfs/sub3

In both examples the filles will hashed 4 times. But the use the same extends? (i don't know if extends is the right word). If you execute "df" you will see that only 1 GB is used.