Missing some ZFS values in sysctl output

[Willem Jan Withagen]

Hoi,

There is this zfs-snmp script that allows one the graph certain things
from a ZFS setup.
The original uses solaris' kstat, but just about all values are in
Sysctl with FreeBSD.

However I seem to overlook the values for:

Original code:
====
def zfs_read(oid):
    return ('counter', kstat("unix:0:vopstats_zfs:read_bytes") / 1024 %
2**32) # 32 bit KB counter

def zfs_readdir(oid):
    return ('counter', kstat("unix:0:vopstats_zfs:readdir_bytes") / 1024
% 2**32) # 32 bit KB counter

def zfs_write(oid):
    return ('counter', kstat("unix:0:vopstats_zfs:write_bytes") / 1024 %
2**32) # 32 bit KB counter
=======

Read and write are available for L2 arc, but for the global values I
seem to miss them.

Are they really not in ZFS?
And is it possible to add them?

Reagards,
--WjW