"Apache Tomcat enjoys the reputation of being a small but very
formidable servlet container capable of handling heavy production
loads. Its most common role probably is as the application server
for lightweight J2EE applications (servlets, plain old Java
objects, and no EJBs). In such a role, it often handles significant
production loads, for which these types of lightweight applications
are best suited.
"Tomcat's default installation, though, is configured to handle
medium loads. Running an application on Tomcat in high-load
environments requires further tuning..."