openldap-1.x vs. openldap-2.x

[Andreas Stollar <andreas@speakeasy.net>]

I just tried to migrate my ldap db to openldap-2.0.11. After a few minor
cleanups in the ldif file dumped from openldap-1.2.11, everything worked.
However, once I loaded up the box in a production environment, the thing
just fell flat on its face, performance was so slow as to be unacceptable.
I had to revert back to openldap-1.2.12, which is incredibly fast. I am
only using the ldap db (right now at least) to authenticate users on our
mail cluster, which runs qmail-ldap.

I was wondering if anyone had any performance figures for 1.x vs. 2.x.? I
tried just about every indexing combination as well as compiling with, and
without threads, and used Berkeley DB 3.1.17 (the redhat RPM)
BerkeleyDB-3.3.11 (built locally from the tarball) and gdbm (again from
the redhat rpm) I am using Redhat-7.1. A few things did make a difference,
but all performed so badly I could not use it. I can't believe that
openldap-2.0.11 really performs this badly, so I figured I must be doing
something wrong. Anyone have any ideas? Anyone convert from 1.x to 2.x
successfully? Copies of my slapd.conf and qmail.schema (slightly
customized) can be found here:
http://www.speakeasy.org/~andreas/ldap/slapd.conf
http://www.speakeasy.org/~andreas/ldap/qmail.schema

Any input would be appreciated, I'll stick with openldap-1.2.12 for now,
but it scares me that is has been relegated to the 'historical' section.

Andreas Stollar
SPEAKEASY.net Senior System Admin