Tomcat configuration recommendations

This topic provides some configuration tips for getting started with your Tomcat application server.

Keep in mind that complete documentation on configuring and using the Tomcat server is available at this URL for the server:

http://localhost:8080/docs/

This topic provides some configuration tips that are specific to the Integrator Server application.

Creating a setenv file

It is recommended that you create a file named setenv.bat (Windows) or setenv.sh (Linux) and place it in the Tomcat bin directory. With this file (which is run by the catalina.bat and catalina.sh scripts), you can change the following Tomcat environment settings with the JAVA_OPTS variable:

You can set the minimum and maximum memory heap size with the JVM -Xms and -Xmx parameters. The best limits depend on many conditions, such as transformations which Information Discovery Integrator should execute. For these types of transformations, a maximum of 1 GB is recommended. For example, to set the minimum heap size to 128 MB and the maximum heap size to 1024 MB, use:
```
JAVA_OPTS="-Xms128m -Xmx1024m"
```
You should set the maximum limit of the PermGen (Permanent Generation) memory space to a size larger than the default. The default of 64 MB is not enough for enterprise applications. A suitable memory limit depends on various criteria, but 256 MB would make a good choice in most cases. If the PermGen space maximum is too low, OutOfMemoryError: PermGen space errors may occur. You can set the PermGen maximum limit with the following JVM parameter:
```
-XX:MaxPermSize=256m
```
For performance reasons, it is recommended that the application is run in Server mode. Apache Tomcat does not run in Server mode by default. You can set the Server mode by using the JVM -server parameter. You can set the JVM parameter in the JAVA_OPTS variable in the environment variable in the setenv file.

The following is an example of a setenv.bat file:

set "JAVA_OPTS=%JAVA_OPTS% -Xms128m -Xmx1024m -XX:MaxPermSize=256m -server"

About database connections

The default installation (without changes to the configuration) uses the embedded Apache Derby DB, and therefore does not need an extra database server. In addition, the installation (as regards to the DB) does not need any subsequent configuration.

Integrator Server configures itself during the first startup. Database tables and some necessary records are automatically created on the first startup with an empty database. In the Sandboxes tab of the Integrator Server Administration GUI, you can check that there is one default sandbox created with one test graph.

Only one Integrator Server instance can work with the embedded DB. If you need more instances, you should configure an external DB.

You will have to determine if the embedded Apache Derby DB is sufficient for your application when you are ready for production deployment. If the Apache Derby DB is not sufficient, you can configure an external DB connection such as Microsoft SQL or Oracle. For details on configuring external DBs, see the Reference Manual for the Integrator Server.