Solaris ZFS Administration Guide

Listing Virtual Device Statistics

In addition to pool-wide I/O statistics, the zpool iostat command can display statistics for virtual devices. This command can be used to identify abnormally slow devices, or simply to observe the distribution of I/O generated by ZFS. To request the complete virtual device layout as well as all I/O statistics, use the zpool iostat -v command. For example:

# zpool iostat -v
               capacity     operations    bandwidth
tank         used  avail   read  write   read  write
----------  -----  -----  -----  -----  -----  -----
mirror      20.4G  59.6G      0     22      0  6.00K
  c1t0d0        -      -      1    295  11.2K   148K
  c1t1d0        -      -      1    299  11.2K   148K
----------  -----  -----  -----  -----  -----  -----
total       24.5K   149M      0     22      0  6.00K

Note two important things when viewing I/O statistics on a virtual device basis:

You can use the same set of options (interval and count) when examining virtual device statistics.