我有一个ZFS备份服务器（Ubuntu 16.04; 32GB内存，4x6TB硬盘，raidz2）。 最近我发现空间有问题。
# zpool list -v NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT pool 21.6T 19.9T 1.76T - 62% 91% 2.30x ONLINE - raidz2 21.6T 19.9T 1.76T - 62% 91% sda5 - - - - - - sdb5 - - - - - - sdc5 - - - - - - sdd5 - - - - - - 看起来几乎所有的空间都被分配了。 我不知道是什么消耗它。 看看卷的大小：
# zfs list -o space NAME AVAIL USED USEDSNAP USEDDS USEDREFRESERV USEDCHILD pool 425G 13.4T 0 140K 0 13.4T pool/backup 425G 742G 0 140K 0 742G pool/backup/avol 425G 69.0G 0 198K 0 69.0G pool/backup/avol/old_dumps 425G 69.0G 0 69.0G 0 0 pool/backup/nnn 425G 517G 0 163K 0 517G pool/backup/nnn/cdvol 425G 5.00G 0 5.00G 0 0 pool/backup/nnn/himvol 425G 98.3G 0 98.3G 0 0 pool/backup/nnn/irvol 425G 33.8G 0 140K 0 33.8G pool/backup/nnn/irvol/smavol 425G 33.8G 0 33.8G 0 0 pool/backup/nnn/menvol 425G 931M 0 931M 0 0 pool/backup/nnn/nevvol 425G 77.9G 0 77.9G 0 0 pool/backup/nnn/scovol 425G 27.4G 0 27.4G 0 0 pool/backup/nnn/vm 425G 274G 0 16.5M 0 274G pool/backup/nnn/vm/123 425G 1.47G 0 1.47G 0 0 pool/backup/nnn/vm/124 425G 9.23G 0 9.23G 0 0 pool/backup/nnn/vm/125 425G 13.5G 0 13.5G 0 0 pool/backup/nnn/vm/126 425G 10.5G 0 10.5G 0 0 pool/backup/nnn/vm/128 425G 16.9G 0 16.9G 0 0 pool/backup/nnn/vm/130 425G 8.96G 0 8.96G 0 0 pool/backup/nnn/vm/131 425G 147G 0 147G 0 0 pool/backup/nnn/vm/132 425G 11.3G 0 11.3G 0 0 pool/backup/nnn/vm/135 425G 39.7G 0 39.7G 0 0 pool/backup/nnn/vm/136 425G 16.0G 0 16.0G 0 0 pool/backup/old 425G 50.5G 0 140K 0 50.5G pool/backup/old/himvol 425G 50.5G 0 50.5G 0 0 pool/backup/telvol 425G 105G 0 105G 0 0 pool/backup2 425G 2.74T 0 140K 0 2.74T pool/backup2/nnn 425G 2.74T 0 140K 0 2.74T pool/backup2/nnn/vm 425G 2.74T 0 151K 0 2.74T pool/backup2/nnn/vm/101 425G 28.0G 0 28.0G 0 0 pool/backup2/nnn/vm/103 425G 38.0G 0 38.0G 0 0 pool/backup2/nnn/vm/104 425G 333G 0 333G 0 0 pool/backup2/nnn/vm/105 425G 526M 0 526M 0 0 pool/backup2/nnn/vm/106 425G 17.1G 0 17.1G 0 0 pool/backup2/nnn/vm/107 425G 17.0G 0 17.0G 0 0 pool/backup2/nnn/vm/109 425G 235G 0 235G 0 0 pool/backup2/nnn/vm/110 425G 321G 0 321G 0 0 pool/backup2/nnn/vm/111 425G 1.11G 0 1.11G 0 0 pool/backup2/nnn/vm/112 425G 73.6G 0 73.6G 0 0 pool/backup2/nnn/vm/114 425G 1.27T 0 1.27T 0 0 pool/backup2/nnn/vm/116 425G 1.31G 0 1.31G 0 0 pool/backup2/nnn/vm/117 425G 19.9G 0 19.9G 0 0 pool/backup2/nnn/vm/119 425G 7.15G 0 7.15G 0 0 pool/backup2/nnn/vm/121 425G 178G 0 178G 0 0 pool/backup2/nnn/vm/122 425G 237G 0 237G 0 0
最近，我closures了重复数据删除并复制了所有卷（zfs send | zfs receive; zfs destroy）以除去重复数据，但仍然存在：
# zpool status -D pool: pool state: ONLINE scan: scrub in progress since Wed Jul 12 11:23:27 2017 1 scanned out of 19.9T at 1/s, (scan is slow, no estimated time) 0 repaired, 0.00% done config: NAME STATE READ WRITE CKSUM pool ONLINE 0 0 0 raidz2-0 ONLINE 0 0 0 sda5 ONLINE 0 0 0 sdb5 ONLINE 0 0 0 sdc5 ONLINE 0 0 0 sdd5 ONLINE 0 0 0 errors: No known data errors dedup: DDT entries 41434395, size 978 on disk, 217 in core bucket allocated referenced ______ ______________________________ ______________________________ refcnt blocks LSIZE PSIZE DSIZE blocks LSIZE PSIZE DSIZE ------ ------ ----- ----- ----- ------ ----- ----- ----- 1 25.3M 2.41T 1.95T 1.99T 25.3M 2.41T 1.95T 1.99T 2 5.00M 469G 340G 347G 11.2M 1.03T 762G 779G 4 7.37M 549G 438G 451G 36.9M 2.69T 2.14T 2.21T 8 1.41M 124G 80.7G 83.5G 14.6M 1.26T 833G 862G 16 281K 16.8G 10.7G 11.5G 5.72M 337G 219G 235G 32 73.7K 4.57G 3.79G 3.96G 3.14M 198G 167G 174G 64 40.5K 2.58G 2.32G 2.41G 3.25M 215G 195G 202G 128 8.49K 358M 272M 298M 1.38M 60.2G 45.7G 50.0G 256 3.22K 201M 171M 180M 1.10M 69.8G 59.7G 62.7G 512 1.46K 56.1M 52.2M 56.9M 1.20M 41.1G 38.1G 42.1G 1K 372 12.5M 10.4M 11.7M 501K 19.5G 16.3G 18.0G 2K 169 7.41M 6.14M 6.78M 468K 20.3G 17.0G 18.8G 4K 64 3.40M 2.69M 2.85M 358K 19.1G 15.0G 15.9G 8K 14 316K 172K 238K 151K 3.37G 1.82G 2.52G 16K 10 35.5K 31.5K 75.6K 206K 738M 667M 1.54G 32K 4 102K 85.5K 105K 185K 4.71G 3.93G 4.79G 256K 2 1K 1K 11.6K 704K 352M 352M 4.00G Total 39.5M 3.55T 2.81T 2.87T 106M 8.36T 6.42T 6.61T
也许这是原因？ 有什么办法来检查使用重复数据删除的数据，并删除它们？ 还有什么可以消耗磁盘空间？
zpool scrub有一些奇怪的东西。 我在6小时前开始（CEST时区），目前的状态是：
scan: scrub in progress since Wed Jul 12 15:48:20 2017 1 scanned out of 20.0T at 1/s, (scan is slow, no estimated time) 0 repaired, 0.00% done
在服务器上加载的时间很长（正常运行时间从2到80），iostat显示100％的磁盘利用率，但没有进程正在运行（除了ssh服务器）。
更新：今天我有近1TB的自由空间。 在服务器上没有做任何事情，也许zfs需要一些时间来清理旧数据？
解决：问题已经消失。 重复数据删除performance在是空的，6,75TB的可用空间！ zfs花了大约6天的时间来清理它。
运行一个python脚本来检测和删除重复的数据文件：
http://code.activestate.com/recipes/362459-dupinator-detect-and-delete-duplicate-files/