[OmniOS-discuss] L2ARC actual size and zpool iostat -v output discrepancy?

[wuffers]

So I only upgraded to r151008 recently, and was wondering whether the new
L2ARC compression was working. After getting an updated arcstat script
which added the l2asize option (which returned a 0), and a few rounds in
IRC which lead me to the correct kstat (zfs:0:arcstats:l2_asize), and an
even more updated arcstat to fix the 0 result..

Now both kstat and arcstat are outputting the same info:
zfs:0:arcstats:l2_asize 864682956800
zfs:0:arcstats:l2_size  1374605708288

arcstat:
read  hits  miss  hit%  l2read  l2hits  l2miss  l2hit%  arcsz  l2size
l2asize
2.7K  2.6K    53    98      53      44       9      83   229G    1.3T
806G
5.1K  4.8K   282    94     282      17     265       6   229G    1.3T
806G
7.3K  7.3K    10    99      10       4       6      40   229G    1.3T
806G
...

But.. why is zpool iostat -v showing me my cache devices using up ~1.25T
(314Gx4), which is close to the 1.3T l2size?

                              capacity     operations    bandwidth
pool                       alloc   free   read  write   read  write
-------------------------  -----  -----  -----  -----  -----  -----
[snip]

cache                          -      -      -      -      -      -
  c2t500117310015D579d0     313G  59.4G     19     15   711K   833K
  c2t50011731001631FDd0     314G  58.1G     18     15   712K   836K
  c12t500117310015D59Ed0    314G  58.8G     19     15   710K   835K
  c12t500117310015D54Ed0    313G  59.7G     18     15   709K   832K
-------------------------  -----  -----  -----  -----  -----  -----

What's with the discrepancy? Is zpool iostat calculating the free capacity
incorrectly now (my cache drives are 400GB)?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://omniosce.org/ml-archive/attachments/20140212/72742471/attachment.html>