Monitoring and Tuning Your Server

Measuring Security Overhead with WCAT

WCAT is a script-driven, command line – based application that tests your server configuration using a variety of predetermined, unvarying workloads. You can use WCAT to test how your server responds to different workloads or test the same workload on varying configurations of the server.

WCAT includes a folder of prepared test workloads; alternatively, you can use it to create your own workloads. WCAT also includes a special option, ssl.testname, which adds SSL protocol settings to any workload test.

A WCAT test simulates clients and servers communicating over a network, and ordinarily requires at least three computers for each test:

At least one computer that simulates a client, which runs one or more virtual clients
One computer that acts as a server
One computer, called a controller, which initiates and monitors the test

Both client and controller can run on one computer. (In fact, all three functions can run on a single computer, but this produces skewed results.)

To produce a realistic test, it is best to associate four or more client computers, each running several virtual clients, with each server. The processors in the client computers should be at least as fast as the processors in the server computer. If they are not, more client computers should be associated with each server computer. WCAT works best if the network that connects the computers has little or no traffic that is not related to the test. It is preferable to use a link dedicated only to the test. A 100 Mbps or faster network is recommended.

See the following: