Sun Java System Web Server 6.1 SP9 Performance Tuning, Sizing, and Scaling Guide

HTTP/1.1-style Workload

In general, it is a tradeoff between throughput and latency while tuning server persistent connection handling. The KeepAliveQueryQuery* directives (KeepAliveQueryMeanTime and KeepAliveQueryMaxSleepTime) control latency. Lowering the values of these directives is intended to lower latency on lightly loaded systems (for example, reduce page load times). Increasing the values of these directives is intended to raise aggregate throughput on heavily loaded systems (for example, increase the number of requests per second the server can handle). However, if there's too much latency and too few clients, aggregate throughput will suffer as the server sits idle unnecessarily. As a result, the general keep-alive subsystem tuning rules at a particular load are as follows: