mattlach
Patron
- Joined
- Oct 14, 2012
- Messages
- 280
Hey all,
I'm just a little confused, hoping someone could help clear things up.
I've got a RAIDz2 array up with 8 drives (I know, not recommended configuration for performance reasons, but it works for me)
Four of the drives are 3TB, and four are 4TB.
Based on that, I'd expect 3*6=18TB of useable space.
Converting from TB to TiB that should be 18*(1000)^4/(1024)^4 = 16.37TiB
So, I expect to have a total of 16.37TiB available.
Now comes the funny part:
The GUI says I have 15.2TiB total.
a df -h shows me:
and zpool list shows me:
That last one is the most crazy!
So, which one of these methods is deemed to be the most accurate (definitely not the last one, unless it is assuming a certain compression ratio) and why is the 16.37 from my calculations not reflected here?
Am I seeing a 1.1TiB loss due to ZFS overhead above what would be expected from double parity?
Appreciate anything that can enlighten me!
Thank you,
Matt
I'm just a little confused, hoping someone could help clear things up.
I've got a RAIDz2 array up with 8 drives (I know, not recommended configuration for performance reasons, but it works for me)
Four of the drives are 3TB, and four are 4TB.
Based on that, I'd expect 3*6=18TB of useable space.
Converting from TB to TiB that should be 18*(1000)^4/(1024)^4 = 16.37TiB
So, I expect to have a total of 16.37TiB available.
Now comes the funny part:
The GUI says I have 15.2TiB total.
a df -h shows me:
Code:
Filesystem Size Used Avail Capacity Mounted on RAIDz2-01 15T 2T 13T 13% /mnt/RAIDz2-01
and zpool list shows me:
Code:
# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT RAIDz2-01 21.8T 2.79T 19.0T 12% 1.00x ONLINE /mnt
That last one is the most crazy!
So, which one of these methods is deemed to be the most accurate (definitely not the last one, unless it is assuming a certain compression ratio) and why is the 16.37 from my calculations not reflected here?
Am I seeing a 1.1TiB loss due to ZFS overhead above what would be expected from double parity?
Appreciate anything that can enlighten me!
Thank you,
Matt