From: DeskNow Knowledge Base
http://www.desknow.com/kb/

Performance tuning
http://www.desknow.com/kb/idx/12/162/article/

This article provides a few tip and strategies to optimize the performance of your DeskNow installation.

Tuning the database

The most important factor in DeskNow's performance is determined by the database.

With few configuration changes, the database performance can be increased considerably, providing a faster experience and allowing a server to host more accounts.

The first step in tuning your Database is to find out which database you're using - if unsure, or if DeskNow was installed by another person.

To find out which database you're using: open the C:\desknowdata\cfg\Database.cfg (/var/desknowdata/cfg/Database.cfg) file, and look at the Url parameter (NB if you find a line preceded by a #, it is commented out, and should be ignored. The file will contain only one line beginning with 'Url').

Reducing the amount of mail processed

Very often a lot of mail received by a mail server is spam. Even when it is correctly identified as spam, it takes up system resources to process and store these emails. With a few simple changes, the amount of spam mail that enters the processing queues can be drastically reduced.

Clustering

Consider scaling DeskNow to a cluster of two or more servers (see the Administration manual at the section 'Clustering and load balancing'). Clustering not only improves performance for systems with many users, but will also provide high-availability and redundancy, so that if one server crashes for any reason, users will still be able to use another server.