also you could find info about no. of connecitons (in the sampe page)
What's the Best Size for my Connection Pool?
As with all other configuration rules-of-thumb, the answer is "It depends." While the optimal size depends on anticipated load and average database transaction time, the optimum connection pool size is smaller than you might expect. If you take Sun's Java Petstore blueprint application for example, a connection pool of 15-20 connections can serve a relatively moderate load (600 concurrent users) using MySQL and Tomcat with response times that are acceptable.