Sun Java System Web Server 6.1 SP12 Performance Tuning, Sizing, and Scaling Guide

HTTP/1.0-style Workload

Since HTTP/1.0 results in a large number of new incoming connections, the default acceptor threads of 1 per listen socket would be suboptimal. Increasing this to a higher number should improve performance for HTTP/1.0-style workloads. For instance, for a system with 2 CPUs, you may want to set it to 2.