I'm trying to get the total bytes written to disk in FreeNAS v9.10 running RAIDz2-0. I went under Reporting > Disk and could see output like:

enter image description here

But I'm not sure what this means. I'm guessing "M" is Megabytes and "Last" is since last reboot?. It's unclear in docs here and here. Is 267M total writes since last reboot?

In terminal I also tried vmstat -p array which didn't offer data needed.

[root@freenas] ~# vmstat -p array
 procs      memory      page                      faults         cpu
 r b w     avm    fre   flt  re  pi  po    fr  sr   in   sy   cs us sy id
 1 1 0   3890M  1881M   275   0   0  28   234 829  878 2078 1804  0  0 99

How do you get the total bytes written for FreeNAS?

It appears iostat is what i should be using because man iostat says "The first statistics that are printed are averaged over the system uptime".
iostat -dI is showing:

[root@freenas] ~# iostat -dI
             da0              da1              da2              da3 
  KB/t xfrs   MB   KB/t xfrs   MB   KB/t xfrs   MB   KB/t xfrs   MB 
 33.51 79317495 2595417.21  33.74 78641558 2591314.42  33.91 78170544 2588457.94  34.01 77875087 2586463.43

But if daX and "X" number is the disk, i'm wondering where the other 4 are.

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