Swap on ZFS Volume still panics?

[Daniel Kalchev]

  Have been using swap on ZFS for a while. 8 GB RAM, in 
/boot/loader.conf only:

vm.kmem_size="12G"

KDE workstation with two 500GB drives in ZFS mirror. Swap volume is

NAME          PROPERTY              VALUE                  SOURCE
storage/swap  type                  volume                 -
storage/swap  creation              Ср  Юни 16 14:17 2010  -
storage/swap  used                  16G                    -
storage/swap  available             58,6G                  -
storage/swap  referenced            3,99G                  -
storage/swap  compressratio         1.00x                  -
storage/swap  reservation           none                   default
storage/swap  volsize               16G                    -
storage/swap  volblocksize          8K                     -
storage/swap  checksum              off                    local
storage/swap  compression           on                     local
storage/swap  readonly              off                    default
storage/swap  shareiscsi            off                    default
storage/swap  copies                1                      default
storage/swap  refreservation        16G                    local
storage/swap  primarycache          all                    default
storage/swap  secondarycache        all                    default
storage/swap  usedbysnapshots       0                      -
storage/swap  usedbydataset         3,99G                  -
storage/swap  usedbychildren        0                      -
storage/swap  usedbyrefreservation  12,0G                  -
storage/swap  org.freebsd:swap      on                     local


Just added compression by the way, haven't yet seen it in action. 
Sometimes, it swaps up to 2-4 GB. Swapping is noticeably slow.

Never had hangs or kernel panics.

Daniel