I've finally gotten around to getting my performance monitoring of
commands back into Listserv.  (I lost it when CMS 5 changed GLOBALV.)
I spend some time looking at performance because we get a lot of
requests, since we are advertised as the focal point for a copy
high volume lists.  One is a degenerative case, NetMonth.  It has
over 4,000 subscribers.  It takes minutes, yes minutes, to add or
delete someone from that list.  Our Listserv was "tied" up for
5 hours on Saturday because of adds and deletes to NetMonth.
(I'm not trying to shift blame to the list owner.  The function is
there, is the easiest way to do it, it should be handled, but it
isn't gracefully)  From my limited view of the performance I am
seeing, I think we need to get some serious numbers on performance
before we put a lot into more Global commands.  The "biggest" used
command on our Listserv is already DIST2, both in terms of number
of times used, CPU time, CPU time per command, I/O, and I/O per command.
I would hate to see more work given to it, without some better
understanding of what the impact to the system is going to be.
 
Harry (with a typical sysprog answer) Williams