Sun Java System Web Server 6.1 SP6 Performance Tuning, Sizing, and Scaling Guide

Thread Pools (UNIX/Linux Only)

Since threads on UNIX/Linux are always operating system (OS)-scheduled, as opposed to user-scheduled, UNIX/Linux users do not need to use native thread pools, and this option is not offered in the user interface for these platforms. However, you can edit the OS-scheduled thread pools and add new thread pools if needed, using the Server Manager.