IIS scalability

Question

I have been tasked recently to estimate number of concurent users that IIS can handle. Unfortunately, I have 0 experience with IIS, so I hope someone will guide me where to look. I hope I will not have to do my own benchmarking in this phase.

I would like to know what is the number of concurrent connections that it can handle. The clients will use either comet/long polling, or polling, depending on the answer. Web application under IIS will be SOAP web service. Service is neither computation nor data intensive.

It will run on todays normal hardware, core2 duo, 4GB ram, no other applications on the box.

Answer 1

This blog post might help with a start.

From that post:

IS6 can easily handle 3,000 concurrent keep-alive connections, assuming you:

• Have sufficient HW resources (like RAM) on the system
• Reconfigure the system (i.e. tweak any applicable limits)
• Run scalable user software that handles the user load (i.e. uses asynchronous IO, not necessarily multi-threaded, has appropriate caches, etc)