Setting up new databases
When setting up new databases, you should ensure sufficient isolation, and set an appropriate number of connections.
During the installation process, you need to create up to three databases: the Core Application database, the Activity Engine database, and (optionally) the Analytics database. These systems should be installed on separate, isolated resources, as described in Database configuration. Although you may be tempted to ignore this recommendation if you have a robust, high-capacity system, you should still seriously consider IO and memory isolation. It's also very important to maintain isolation of security roles.
The maximum number of incoming connections must be set to accommodate the sum of max connections across all web servers, plus a small administrative overhead.
For example, if 5 application nodes are set to from 50 to 150 max connections, the database should be able to allow as many as (5*150)=750 connections from the application DB, +n for administrative connections should all connections be in use. A typical overage is +5–10 connections.
Analytics databases only require connections for the application server listeners and administrative users. Typically, the maximum connections number is much lower than the application database requires. The Activity Engine database default is a maximum of 50 connections. This typically does not need to be increased.