We have recently begun stress testing our web site and noticed that as soon as we attempt 41 concurrent connections against IIS 4.0, many of the requests are not responded to by the server. We are not invoking an .ASP page, only a simple “Hello World” .HTML file. This same behavior occurs on multiple boxes, each a dual processor system. 0 – 40 works fine. 41 is the magic number where things fall apart. I’ve tried various metabase and registry setting all to no effect. Have installed Apacheand don’t have this problem so I don’t think it’s network infrastructure related. If calling an ASP page, an HTTP 500 error is returned to many of the connections opened by the load test tool. HTTP Result Code not returned is the error returned when using ASP or HTML files as the target of the load test with > 40 users.
