ZFS Volume (6 drives) raidz1-0

[shackrock]

I've got a ZFS volume on FreeNAS 8.3.1 (latest). It's got 6 drives in a raidz1-0 array.

I'm wondering if there is a % storage limit I should be adhereing to... (like on my HDD's at home, I try not to go over 90%)...

Here's where I'm at now:
8.1 TiB (91%) 805.3 GiB 8.9 TiB

Any thoughts?

Thanks

 

[cyberjock]

You should try to keep it below 85%, and definitely 90%. At 90%(I think that's what it was) ZFS changes the way it stores files from fastest to most efficient.

 

[shackrock]

You should try to keep it below 85%, and definitely 90%. At 90%(I think that's what it was) ZFS changes the way it stores files from fastest to most efficient.

Ok, so I'll have some slow downs for sure good to know

What about disk reliability, am I risking any early failures on disks? With my single 2.5" HDD it was always 'you're making the disk head work harder when you're over 90%!' Is there a similar concern in this case?

Thanks

 

[cyberjock]

If you are going over 90% there are serious(and basically permanent) consequences. You will make the drives work harder(which could potentially wear them out sooner), but you will also see significant fragmentation resulting in significant performance penalty. Since you can't defrag the zpool there is no cure when the fragmentation gets very out of hand except to delete the zpool and start over. Scrubs will take significantly longer because of the fragmentation, iscsi devices may start failing because of timeouts. It just opens a can of worms that only gets worse and cannot ever be closed.

Honestly, you should seriously reconsider your zpool and what data you store on it. You'd be much better off adding another disk or 2 to the zpool than thinking you're going to be able to "get by" with a zpool that is that full. Even Windows gives warnings at 20% free space and alerts at 15%.