illumos gate

Currently, kstat is woefully inefficient on fully specified kstats, e.g.:

[root@headnode (bh1-kvm6) /var/tmp]# ptime /usr/bin/kstat -p -m unix -n system_misc -s boot_time > /dev/null

real        0.312228467
user        0.267776579
sys         0.044044015

The reason for this is a simple logic error: when filtering out kstats, kstat(1) mistakenly reads any kstat that matches the specified module or the specified name, instead of the specified module and the specified name. Making the two character change results in a significant speedup:

[root@headnode (bh1-kvm6) /var/tmp]# ptime /var/tmp/kstat -p -m unix -n system_misc -s boot_time > /dev/null

real        0.019144410
user        0.006114901
sys         0.012684514