You can monitor the effect of ISAPI and CGI applications on the overall performance of your server. In general, CGI applications use significantly more processor time and memory than equivalent ISAPI DLLs. You can measure this disparity on your servers by using the general server monitoring techniques developed in Chapter 5, "Monitoring Virtual Memory" and Chapter 6, "Preventing Processor Bottlenecks."
This section suggests two approaches to monitoring the effects of dynamic page-generating applications on general server performance:
Using Performance Monitor to monitor server performance while running ISAPI extensions and CGI applications on your server.
Using WCAT, the Web Capacity Analysis Toolkit, to simulate the effects of CGI and ISAPI applications on your server.
You can also use Performance Monitor to monitor your WCAT tests. The following sections explain these monitoring techniques in more detail.