Sergej31231
Dabbler
- Joined
- Apr 26, 2017
- Messages
- 14
Good evening,
I try to setup a test backup storage with FreeNAS. If FreeNAS is going to work fine, I would like to buy certified hardware. But unfortunately
I got stuck in deduplication. Either I configured something wrong or the ZFS deduplication feature is N O T on block level.
Please Look at this:
So I have 4 files, they all are nearly identical. Only one file has an additional char. Deduplication ratio must have been much more than 3.00x.
I think it might be about > 3.90. I did everything in a right way: i did not change the files, I copied them etc...
Because of not knowing a lot about the block sizes, I repeated this experiment with BIG files, with the same poor ratio.
But experiments with reproducing identical files without changing their content have worked as expected.
I am pretty sure that deduplication is file level. So why everyone says that FreeNAS zfs deduplication is block level?
File level deduplication makes no sense for me, because I have no Identical files (veeam backup files) but I have a lot of identical blocks!
Sorry for my bad english --> I am a russian from germany :D
I'm looking forward to your reply
Thank you &
Good evening :)
I try to setup a test backup storage with FreeNAS. If FreeNAS is going to work fine, I would like to buy certified hardware. But unfortunately
I got stuck in deduplication. Either I configured something wrong or the ZFS deduplication feature is N O T on block level.
Please Look at this:
Code:
drwxr-xr-x 2 root wheel uarch 6 Apr 27 05:57 ./ drwxr-xr-x 3 root wheel uarch 3 Apr 27 05:51 ../ -rw-r--r-- 1 root wheel uarch 4 Apr 27 05:55 1 -rw-r--r-- 1 root wheel uarch 4 Apr 27 05:56 2 -rw-r--r-- 1 root wheel uarch 5 Apr 27 05:57 3 -rw-r--r-- 1 root wheel uarch 4 Apr 27 05:56 4 [root@srv/ibm/dataset]# cat * 123 123 1234 123 ... [root@srv /ibm/dataset]# zpool list NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT freenas-boot 136G 653M 135G - - 0% 1.00x ONLINE - ibm 3.97T 492K 3.97T - 0% 0% 3.00x ONLINE -
So I have 4 files, they all are nearly identical. Only one file has an additional char. Deduplication ratio must have been much more than 3.00x.
I think it might be about > 3.90. I did everything in a right way: i did not change the files, I copied them etc...
Because of not knowing a lot about the block sizes, I repeated this experiment with BIG files, with the same poor ratio.
But experiments with reproducing identical files without changing their content have worked as expected.
I am pretty sure that deduplication is file level. So why everyone says that FreeNAS zfs deduplication is block level?
File level deduplication makes no sense for me, because I have no Identical files (veeam backup files) but I have a lot of identical blocks!
Sorry for my bad english --> I am a russian from germany :D
I'm looking forward to your reply
Thank you &
Good evening :)
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