file system level iostat for zfs??

Hi Experts,  Does anyone knows how to investigate which file system is making IO on a busy zpool? both zpool iostat and iosnoop D script show only at zpool level. I need the statistics at file system level. Any help is appreciated.

Thanks, Alex

# zpool iostat -v k2ldom 5 100
               capacity     operations    bandwidth
pool        alloc   free   read  write   read  write
----------  -----  -----  -----  -----  -----  -----
k2ldom       237G  41.2G     16    625   130K  3.54M
  mirror     237G  41.2G     16    625   130K  3.54M
    c1t2d0      -      -      4    286  77.4K  3.54M
    c1t3d0      -      -      4    286  77.7K  3.54M
----------  -----  -----  -----  -----  -----  -----

# ./iosnoop -v