OpenLDAP MDB vs HDB performance

Revision as of 21:39, 21 February 2013 by Quanah (talk | contribs)

Admin Article

Article Information

This article applies to the following ZCS versions.

ZCS 8.0 Article ZCS 8.0

Zimbra OpenLDAP Server

Performance differences between the mdb and hdb backends for OpenLDAP

Using real-world client data, I've compiled some brief performance differences between using the mdb and hdb backends to OpenLDAP with Zimbra. This particular client has 25,208 entries in their LDAP database. I dumped their accesslog and converted it to LDIF to give me a full weeks worth of real change data, and then ran that back against the database. This results in approximately 28,000 modifications performed against the DB.

Database load

This is the amount of time to load the database using slapadd -q

mdb: 0m11.237s
hdb: 0m38.727s

Advantage: MDB. It is 3.45 times faster loading the data than hdb.

Database size

Size of database on disk after slapadd completes. For hdb, this includes the hdb cache as well as db size. mdb has no cache.

mdb: 296MB
hdb: 627MB

Advantage: MDB. It is 2.11 times smaller than the hdb database.

Search time

This is the time to search the entire db via slapadd. Note that with hdb, since it has to preload the cache, two times are given. cold (Cache not loaded) and hot (cache loaded). mdb never needs to preload the cache.

mdb: 0m1.435s
hdb cold: 0m5.304s
hdb hot: 0m3.103s
Verified Against: ZCS 8.0 Date Created: 2/21/2013
Article ID: Date Modified: 2013-02-21

Try Zimbra

Try Zimbra Collaboration with a 60-day free trial.
Get it now »

Want to get involved?

You can contribute in the Community, Wiki, Code, or development of Zimlets.
Find out more. »

Looking for a Video?

Visit our YouTube channel to get the latest webinars, technology news, product overviews, and so much more.
Go to the YouTube channel »

Jump to: navigation, search