[Kolab-devel] Re: OpenLDAP performance issues

[Dieter Kluenter]

Hi,

Steffen Hansen <steffen at klaralvdalens-datakonsult.se> writes:

> On Friday 20 May 2005 10:39, Dieter Kluenter wrote:
>
>> I think there is no need to update to OpenLDAP-2.2.26,
> [...]
>> >> msg4421:
>> >> LDBM is definitly NO choice, nor will be BerkeleyDB-4.3.27.
>
> Can you explain why upgrading to bdb-4.3.x and openldap-2.2.26 is not a 
> good idea?
>
> I am getting more and more surprised over how badly openldap/bdb is 
> behaving. How can certain config parameters which are supposed to be 
> for tweaking performance cause data corruption when they are not set to 
> the "right" values?

As you know, OpenLDAP is a complete framework of frontends, backends,
SDK and tools to run a directory server. There are plenty of RFC's
which describe the operations of a DSA but none which describes the
backends and storage of relevant data.
Thus the developers of OpenLDAP have to rely on the RDBM vendors,
their design and configuration tools. The RDBM of choice is
BerkeleyDB which offers a comprehensive SDK and documentation. While
BerkeleyDB can be found in a mobile phone as well backend for large
SQL databases, the default configuration of BerkelyDB is based on the
needs of rather small applications, but it is highly configurable to
meet individual requirements.
The  position of OpenLDAP Project is, that a framework is provided and
it is up to the individual administrator to design and configure a
directory server and one or more backends to his individual needs.
While slapd.conf(5) provides some basic options to configure a database
backend, BerkeleyDB offers much more additonal options. All OpenLDAP
documentation points to the appropriate BerkeleyDB docs.

Upgrading to BerkeleyDb-4.3.27 is not advised yet as there are some
locking issues with transactional logs, patches have been provided to
Sleepycat.
Between OpenLDAP-2.2.23 and OPenLDAP-2.2.26 only minor bufixes have
been applied to slapd, back-bdb and back-hdb, major improvements have
been applied to syncrepl, back-ldap and some overlays.

-Dieter

-- 
Dieter Klünter | Systemberatung
http://www.dkluenter.de
GPG Key ID:01443B53