While that script claims to be a /bin/sh script it contains a bashism:
root@mykerinos:/usr/share/doc/samba-doc/examples/perfcounter> checkbashisms perfcountd.init
possible bashism in perfcountd.init line 50 (should be 'b = a'):
if [ "$pid" == "" ]; then
Even though my shell skills are limited I can propose using "-z"...See attached patch
Created attachment 3834 [details]
Fixed in all branches with 73875cd3 (master) and friends.
Thanks for the patch!