Re: Slapd running very slow

On Tue, Apr 21, 2015 at 08:52:29PM +1000, Geoff Swan wrote:

I have an ldap server that appears to slow down significantly even under moderate load, and wondered if there were any suggestions as to where to look.

Using openldap-2.4.40 with mdb backend, on a dual Xeon (6 cores each) server with 128GB ram. Linux kernel 3.13, separate ext4 db volume (SAS). Slapd configured with 48 threads.

The problem appears that as soon as there are a handful of write operations, slapd appears to stall. Binding to the ldap port takes many seconds (instead of instant), and the slapd process appear to occupy 100% of a single CPU core.

What does your config file look like?

In particular, what does this setting look like for you:

# Threads - four per CPU threads 8