This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
The online book Java Platform Performance has some basic rules regarding IO performance, along with ideas on how to measure and compare throughput. The upper bound on throughput is going to be your network, and there's not much tweaking Java code can do a bout that.