(UFS) Volume sizes

[Mailstorm]

Going to be brief.

2TB HDD
UFS filesystem (Because computer is garb. Using FreeNAS as a possible learning opportunity)

Made a UFS volume the size of the entire disk. Said 1.8TB usable. No big, I know why that is. But after putting 500GB of data on it, I noticed the free space available is 200GB off. Is this a bug or am I not understanding something?

 

[cyberjock]

Good question. I don't have the answer since I've never used UFS. You'll probably find that most people here don't use UFS, so you are probably on your own. :(

I don't think it's off though. The 1.8TiB and 1.1TiB could be nothing than rounding errors. For example, you could have gone from 1.76TiB (which rounds to 1.8TiB) to 1.147TiB (which rounds down to 1.1TiB). But your used is 522.3GiB which makes me think you are using 500GB (plus 22.3GB of overhead).

Not sure what your long-term goals are for FreeNAS but UFS is already removed from FreeNAS 9.3. So if your plan was to learn (and then later use) this system with this hardware, you might need to consider alternatives now. It's very likely that 9.2.1.8 (or 9.2.1.9 if it gets released) will be the end of the road for UFS. In any case, 9.3 definitely won't have UFS support.

 

[Mailstorm]

I said 500GB as a round off. The used amount is correct. Using UFS because from what I read, ZFS is kind of a ram dependent filesystem. This is just run on some old computer with only 1GB of ram. It's main purpose is just store movies then later let my raspberry play from it. So far, it's doing it's job well.

 

[Ericloewe]

I said 500GB as a round off. The used amount is correct. Using UFS because from what I read, ZFS is kind of a ram dependent filesystem. This is just run on some old computer with only 1GB of ram. It's main purpose is just store movies then later let my raspberry play from it. So far, it's doing it's job well.

1GB of RAM has been problematic with UFS, so you may be dealing with one of those little gremlins that come out when the RAM runs out.

 

[cyberjock]

You're going to need 2GB of RAM (and 4 would be better) if you plan to stick with UFS. 1GB of RAM is below the minimum requirements per the docs even for UFS.

 

[Mailstorm]

Yeah alright! Running below minimum! I'm sure I can find an extra gig around the house. Thanks for replies.

 

[cyberjock]

Just remember, that after 9.2.1.x is done (which is about 45 days or so from now) you'll never see any security updates or anything that you can fix without being a programmer yourself.

To be honest, I'd recommend you look at other OSes that can do what you need them to do. Using an OS that will certainly have unpatched security problems later isn't a good way to go. ;)

 

[Mailstorm]

Yeah I'll probably change to something else or do some upgrades. Like I said, I just did this for a possible learning opportunity.

 

[cyberjock]

One recommendation is to look at NAS4Free. I'm not a pro with their OS, but their minimum requirements with ZFS are 2GB of RAM I believe. ;)

 

[Mailstorm]

Looks nice. I'll probably end up using that. Just have to transfer all those files back over a 100Mbp/s connection. Then upload again.

 

[willnx]

I don't think it's off though. The 1.8TiB and 1.1TiB could be nothing than rounding errors. For example, you could have gone from 1.76TiB (which rounds to 1.8TiB) to 1.147TiB (which rounds down to 1.1TiB). But your used is 522.3GiB which makes me think you are using 500GB (plus 22.3GB of overhead).

I don't think this is a rounding error by FreeNAS:

1.147Tib -> 1.2611TB
522.3GiB -> 560.815 GB -> .560815 TB (yay! base ten conversions!)

1.2611
+0.560815
-------------
1.821915 TB -> 1.657002 TiB

Which would round to 1.7 TiB. I really hope that FreeNAS doesn't yo-dawg rounding, which might lead to something like this...


I wonder if this weird number in UFS is related to the FreeNAS ZFS known issue:

"The available space reported in the parent zpool may not reflect reality and can be confusing
because the available space represented by datasets or zvols can exceed that of the parent zpool."

 

[cyberjock]

Don't know.. could be overhead with UFS. There's several factors and my "give a crap" factor with UFS is nearly zero since it's dead. Even ZFS can have horrible overhead if you are silly. For example, if you do 512-byte blocks, 100GB of data will take up 2TB. Yes, 2TB!