nicx Posted February 23 Share Posted February 23 (edited) Hi, i have turned on ZFS compression on a new array with 1 3tb hdd without parity disk. After turning on, I copied about 2,5 tb data from another identical 3tb disk (unassigned, xfs, without compression) When looking on the compression rate, its abaou 1.7. But when looking on the disk usage, its exactly the same for the zfs disk in the array and the xfs disk unassigned. In my expectation the used disk space should differ in relation to the compression rate. Whats wrong? Edited February 23 by nicx Quote Link to comment
JorgeB Posted February 23 Share Posted February 23 25 minutes ago, nicx said: When looking on the compression rate, its abaou 1.7. But when looking on the disk usage, its exactly the same for the zfs disk in the array and the xfs disk unassigned. That doesn't make much sense, are you sure there isn't any other data on the disk? Post the output of: zfs get all <pool name>/<dataset> | grep compress and zfs list -t all Quote Link to comment
nicx Posted February 23 Author Share Posted February 23 (edited) here it comes: root@nas:~# zfs get all disk1/backup | grep compress disk1/backup compressratio 1.63x - disk1/backup compression on inherited from disk1 disk1/backup refcompressratio 1.63x - root@nas:~# root@nas:~# zfs list -t all NAME USED AVAIL REFER MOUNTPOINT cache 545G 377G 248K /mnt/cache cache/appdata 70.8G 377G 70.8G /mnt/cache/appdata cache/domains 56.3G 377G 56.3G /mnt/cache/domains cache/icloud 378G 377G 378G /mnt/cache/icloud cache/isos 14.3G 377G 14.3G /mnt/cache/isos cache/share 1.97G 377G 1.97G /mnt/cache/share cache/system 23.7G 377G 23.7G /mnt/cache/system disk1 2.30T 341G 184K /mnt/disk1 disk1/backup 2.30T 341G 2.30T /mnt/disk1/backup root@nas:~# and yes, there is no other data on the disk: root@nas:~# ls -la /mnt/disk1/ total 17 drwxrwxrwx 3 nobody users 3 Feb 23 04:40 ./ drwxr-xr-x 10 root root 200 Feb 22 13:46 ../ drwxrwxrwx 5 nobody users 5 Feb 22 19:50 backup/ root@nas:~# root@nas:~# Edited February 23 by nicx Quote Link to comment
JorgeB Posted February 23 Share Posted February 23 Can't explain that, but something must be going on. Quote Link to comment
nicx Posted February 23 Author Share Posted February 23 (edited) oh shit... I think I found my mistake by myself: I copied the data via the webgui of unraid (Dynamic File Manager). The source data includes a lot of symlinks. I think all symlinks are now "real data" and no more just links. That is why the data is now a lot bigger on the destination disk. Funny coincidence that the compressed data has an identical size as the source uncompressed data with symlinks Edited February 23 by nicx Quote Link to comment
nicx Posted February 23 Author Share Posted February 23 ok, next question: how should I copy the data preserving the symlinks? and because its a lot of data, how to do it in a way that the process survives even. when quitting the ssh shell for example? Quote Link to comment
JorgeB Posted February 23 Share Posted February 23 15 minutes ago, nicx said: ok, next question: how should I copy the data preserving the symlinks? Sorry, can't help with that, never used them. Quote Link to comment
nicx Posted February 23 Author Share Posted February 23 ok just in case someone encounters the same "problem", I now use a user script and run it in the background: rsync -av /mnt/disks/backup/* /mnt/user/backup/ seems to work so far as expected. Quote Link to comment
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