slapadd filching memory

[Jon Roberts <jon@mentata.com>]

Openldap 2.1.23
BDB 4.1.25
RH9

I recently added a very large amount of data to a fresh installation:
about 200K entries with significant text and lots of interrelationships.
The ldif file itself was over 11 Mb. I used slapadd.

I monitored memory during the process. I saw free physical memory
descend from 880 Mb to under 10 while disk cache grew from 110 Mb to 830
and disk buffers grew from 10 Mb to 60. Then came the traditional dance
of swapping memory around for each operation and moving at the pace of a
sedated snail. On a final run it amused me to let the process keep
going, and I'm happy to report that (after many hours) all the data did 
eventually load successfully. Searches on my fat new store perform 
admirably.

The problem is that the memory is not released, neither during the
slapadd (which would've helped), nor after the process is completed,
(successfully or not). Starting and stopping slapd does nothing. I have
to restart the machine to get the memory back. I fiddled with DB cache
values (4 Mb in a single block seemed to work best); that helped
efficiency somewhat but memory keeps disappearing in the same manner.

My question: is this normal, something that could come from a
misconfiguration, or ITS territory warranting further investigation? 
Could this be related to the other BDB discussion?

It may just be all my doing, but I would appreciate any advice on where 
to start looking for a fix. TIA.

Jon Roberts
www.mentata.com