back-bdb performance/configuration: Suggestions?

[Frank Swasey <Frank.Swasey@uvm.edu>]

Hey folks,
  I've read all I can find to read.  I think I've done my homework.  But 
it still performs like a dog.  So, I'll describe what I have and then 
ask for suggestions on how to improve it.

Machine:
  600MHz Pentium III, 256MB memory, 1 20GB IDE drive

OS:
  RedHat Linux 8.0

OpenLDAP:
  2.1.17 
	built on the system
	compiled with LDBM/Berkeley and BDB

BDB: 4.1.25 patch 1

Testing: Load the same ~55000 entry LDIF file (hierarchically sorted) 
five (5) times (using slapadd) and average the numbers.

Both back-ldbm and back-bdb were configured with the same indexes in 
slapd.conf.

back-ldbm had the following DB_CONFIG file:
set_cachesize 0 104857600 2
set_flags DB_TXN_NOSYNC
set_lg_bsize 2097152

back-bdb had the following DB_CONFIG file:
set_cachesize 0 104857600 2
set_flags DB_TXN_NOSYNC
set_lg_bsize 2097152
set_lg_regionmax 262144
set_lg_dir /usr/local/ldap/dbtmp
set_tmp_dir /usr/local/ldap/dbtmp

back-ldbm used /usr/local/ldap/ldap.ldbm as the directory
back-bdb used /usr/local/ldap/ldap.bdb as the directory

back-bdb:
slapadd -c /etc/openldap/slapd.conf.bdb -l sample.ldif averaged 45m09s

back-ldbm:
slapadd -c /etc/openldap/slapd.conf.ldbm -l sample.ldif averaged 10m24s

So, obviously, 4.5x1 is not a good ratio.  Also, obviously, this 
hardware is not up to doing a slapadd of that many entries using 
back-bdb.  What is recommended to improve the performance of back-bdb?  
More memory?  More spindles?  Stick with LDBM?

Thanks,
-- 
Frank Swasey                    | http://www.uvm.edu/~fcs
Systems Programmer              | Always remember: You are UNIQUE,
University of Vermont           |    just like everyone else.
                    === God Bless Us All ===