Load test for 1000 concurrent users

Question

We are planning to use Visual Studio 2010 load test for doing stress test for our app. We like to find out whether our MVC3 app can handle 1000 concurrent users or not.

How many physical machines do we need for that?

The current plan that we have in mind is as below.

1. Server 1 ( Web Server + MS SQL ) : This server is for hosting our application.
2. Server 2 ( Test Controller + its database)
3. Machine 1 (Test agent 1 for 200 concurrent users) * 5

So, seems like we will need 7 physical machines. Are we over-estimating about physical machines? Any idea for load testing 1000 concurrent users would be appreciated. Thanks!

Answer 1

According to my experience on load testing through Visual Studio 2010 I suggest:

1. On server2 you can also add one Test Agent. Controller is not a heavy process. Its work is just sharing the tests among the agents and control them.
   It also collects the Data and Diagnostics, however I suggest to follow this MSDN post and not use them.
2. I think that 5 agents for 1000 users are too many. I am able to run about 700-800 users per agent. Of course that depends from the hardware and the Unit Tests/ Web Performance Tests you use on your Load Tests.
3. Unless this is your production deployment scenario for your project, I'd suggest on server1 to separate the Web Server from your Db because on load testing both will need more CPU and Memory.