In looking for ways to get our Listserv 1.8d installation to
use less memory, I saw in the go.user file that one can set
DBRINDEX=0 to disable reverse indexing. I run Listserv under
a Tru64 Unix environment where the default is "DBRINDEX=1"
in go.user.

I reading through the documentation on LSoft's Web site,
the system admin guide for 1.8d refers to the release notes
for 1.8c for a "discussion" on reverse indexing. I search
both sets of release notes, but I couldn't find anything
about reverse indexing and what the consequences are of
turning it off.

Can someone please explain to me what reverse indexing is
and what the consequences are if I disable it?