Re: slow queries on huge directory or slapd crash

["Probst, Carsten" <carsten.probst@net-m.de>]

hi howard,

On Tue, 2005-02-01 at 02:52 -0800, Howard Chu wrote: 
> 1) When starting out with a new installation, use the newest stable 
> release available. OpenLDAP 2.1 is no longer supported, 2.1.30 was 
> released last April and there have been numerous features and fixes 
> added since then. The current release is always linked from the 
> www.openldap.org web site. Use it.

i completely agree to this point, but in our enterprise unfortunately i
cannot "play" around with different versions (due to politics, policy
and centralized management etc... there is a lot behind it). we already
run several other 2.1.30 servers which perform very well. therefore i
cannot use the latest version. this is why i had to use 2.1.30. i
already updated our much older servers from 2.1.12 to 2.1.30 last year.
i assume management would not accept another update (downtime).

2.1.30 should also be able to handle this problem

> 2) Read the documentation on the www.openldap.org web site including the 
> Administrator's Guide and the FAQ. There is plenty of information and 
> advice on how to configure the software for best performance. First tip, 
> don't use back-ldbm, use back-bdb or back-hdb. Either one can handle a 
> 4GB database with no slowdown, once properly configured.

if you say don't use ldbm, can you explain why? 

is it due to ldbm puts the whole entry as a blob in a table
(id2entry.dbb?) shared by all entries regardless of the objectclass and
have additional tables that act as indices for the first table
(postalCode.dbb, gender.dbb etc...)? this point is not quite clear for
me yet.

if you can point me to a location on the internet where is explained
exactly the differences between the backends (not just bdb is a high
performance db backend) you would make me a more happy man :-)

thanx a lot,
carsten