I created a 3 * 16tb disk pool,
then later extended 3 times (via new extend feature) with 3 * 18tb disks.
sudo zpool list -v
gives me 98tb pool size for my-pool
-size : 98tb
-alloc : 35tb
-free : 63tb
But in Truenas (GUI) i have :
-usable : 65tb
-used : 23tb
-awalable : 42tb
This is a new Truenas instance, and i just did these operations.
As this is a raidz1 using mixed capacity disks, with 6 disks,
i expected :
5 * 16 = 80tb usable,
23tb used,
and 80-23=57tb free.
Did i miss something ?
What should be the correct numbers ?
Is there something to do after extending pool with new disks ?
Best regards 
