ASP.NET concurrency problem

Hi,

I have an ASP.NET application that can print crystal report as PDF and display on client browser. For some reason, this applicaiton is called by another ASP application right now.

When only single user use this application, the PDF display in a few seconds. However, doing a stress test on it quickly disclose some serious problem.

I use a testing ASP to call the ASPX application, which in turn will call a COM+ component to generate the PDF using CR.NET control.

The testing ASP will loop 10 times and I expect it will popup 10 windows of pdf, but indeed, only the first two can run (and slow), other windows just waiting. It seems that it is processed two by two.

Then I expand to use four machines to run the testing program. I have log in both ASPX (IIS) side and COM+ side, and I notice that after the call reaching the ASPX, it is somehow waiting for over 40s before it goes to the COM+, just like it is queued for processing.

Do anyone have idea on such case? Is there any sever settings need to be change?

Thx!