OpenSolaris build 128 now availble - zfs dedup in it
By Roman Ivanov-Oracle on Dec 03, 2009
I've being waiting for this update to try deduplication of zfs. Being
knowing that a lot of files will be written as result of image update I
set zfs compression
including rpool file system (except swap and dump) before doing update.
Zfs compression on my home files already being for one month and proved
to save space/time/power.
Here what I have with zfs compression after all.
$ zfs get -r compressratio NAME PROPERTY VALUE SOURCE rpool compressratio 1.14x - rpool/ROOT compressratio 1.05x - rpool/ROOT/b127 compressratio 1.93x - rpool/ROOT/b128a compressratio 1.05x - rpool/roman compressratio 1.18x -
Now updating image. To get recent bits
$ pfexec pkg image-update --be-name b128a
Reboot in new boot environment crossing fingers ;)
To update zfs to most recent version
$ pfexec zpool upgrade rpool
Remembering old problem I did in advance. Check device name of your zfs.
$ pfexec installgrub -m /boot/grub/stage1 /boot/grub/stage2 /dev/rdsk/c4t0d0s0
First hours impression:
1. time slider daemon is broken. Bug and fix here.
2. Firefox now 3.5.5
3. zfs now have deduplication.
$ zfs get dedup rpool
I am going to set it to sha256,verify. The reason for verify is that I am paranoid about my data. I do believe that:
- If you have files born as result of cp then it is fine to no verify. In this case you do believe that you have identical files.
- In my case data comes from different sources. If two blocks got the same sha256 then I do believe that it is collision. So I would like to verify if they are actually the same.
$ pfexec zfs set dedup=sha256,verify rpool $ pfexec zfs set dedup=off rpool/swap $ pfexec zfs set dedup=off rpool/dump
Time and Math will prove who is right. Anything that can possibly go wrong, does.