XigmaNAS

Is there a way to change the partition size when you format a drive as a zfs storage device? I want to use an older ssd that probably doesn't have great cleanup routines, so under provisioning it by 50% or so should keep it working properly for a long time.

please google a bit, there are a lot of results:

http://serverfault.com/questions/238675 ... -l2arc-use

http://forums.freenas.org/threads/how-t ... ion.11824/

I would not worry about it. If the zil device dies, it will just use a pool based zil, and your performance will go down. Then you get a new drive. If you have a good brand, they will last longer than you think. I have some old Intel ssds that have been running 24/7 for YEARS!

From my own experience it looks like using an old SSD for ZIL may improve the performance, definitely it will not degrade it. It is however a completely different story if it comes to the old SSD L2ARC, which may decrease the performance in some scenarios. For example 6 way mirror pool performs much better on its own than the same pool with an old SATA2 SSD. The reason for that is simple, the data gets written first to the RAM, then L2ARC and then the drives itself, that pool is as fast as the slowest device (old SSD). Once the L2ARC gets removed the pool performs much faster.