Setup
test done on Synology DS-220+ 7.2.2 (geminilake)
SHR 2x18TB HDD (RAID1)
how to get jdupes on Synology
root@storage:~# grep -e product_version -e platform_name /etc/synoinfo.conf platform_name="geminilake" last_show_upgrade_mask_in_login_product_version="7.2.2"
https://synocommunity.com/package/synocli-file
State before deduplication
root@storage:~# df -h /volume1 Filesystem Size Used Avail Use% Mounted on /dev/vg1000/lv 16T 12T 4.1T 75% /volume1 root@storage:~# mount |grep /volume1 /dev/mapper/vg1000-lv on /volume1 type btrfs (rw,nodev,relatime,ssd,synoacl,nospace_cache,auto_reclaim_space,metadata_ratio=50,syno_allocator,subvolid=257,subvol=/@syno)
execute deduplicate of backup folder
root@storage:~# jdupes --one-file-system --dedupe --recurse --size /volume1/backup/ Scanning: 761995 files, 109877 items (in 2 specified) Progress [138877/761995, 32742 pairs matched] 18% ...
on backup folder jdupes processing take 7.5h
results is +0.3TB
root@storage:~# df -h /volume1 Filesystem Size Used Avail Use% Mounted on /dev/vg1000/lv 16T 12T 4.4T 73% /volume1
root@storage:~# btrfs filesystem du --summarize --human-readable /volume1/backup/
Total Exclusive Set shared Filename
1.58TiB 995.21GiB 293.23GiB /volume1/backup/
deduplicate shared folder
root@storage:~# jdupes --one-file-system --dedupe --recurse --size /volume1/backup/
took about 55 hours
add about 2.6TB of free space
root@storage:~# df -h /volume1 Filesystem Size Used Avail Use% Mounted on /dev/vg1000/lv 16T 8.7T 7.1T 56% /volume1
So total free space gain is 3TB (from 12TB used) and 62 hours of duduplication run
