What are good load testing tools for IIS 7 web applications?

The title says it all. I'm looking for a good set of tools that I can use to load test a web application on IIS 7 before deployment.


There are a couple of good tools available:

Not free, but excellent if you are doing this professionally is Visual Studio Team System Test Load Agent. MSDN covers how to set it up and run it here: Controllers, Agents, and Rigs. You can download a trial here:

  • Visual Studio Team System 2010 Test Load Agent Beta 1
  • Visual Studio Team System 2008 Test Load Agent (90-day Trial)

As far as free tools...

Web Capacity Analysis Tool (WCAT):

Overview: Web Capacity Analysis Tool (WCAT) is a lightweight HTTP load generation tool primarily designed to measure the performance of a web server within a controlled environment. WCAT can simulate thousands of concurrent users making requests to a single web site or multiple web sites. The WCAT engine uses a simple script to define the set of HTTP requests to be played back to the web server. Extensibility is provided through plug-in DLLs and a standard, simple API.

Features:

  • HTTP 1.0 and HTTP 1.1 capable
  • Supports IPv6 Multithreaded Support
  • Supports generating stress from multiple machines
  • Extensible through C plug-in
  • DLLs Supports Performance Counter integration
  • Measures throughput and response time
  • Supports SSL requests
  • NTLM Authentication request support
  • Easily supports testing thousand of concurrent users

Download the x86 version here, and the x64 version here.


I believe Apache Bench is pretty widely used for this sort of thing and can be used without any problem against other webservers. It's command-line based, so it should be pretty easy to script into your test suite or pre-deployment scripts.

http://httpd.apache.org/docs/2.0/programs/ab.html


I have used Web Application Stress Tool before. I'm wondering if this is a pretty standard tool to use, and if there are better alternatives

(WAS) can be downloaded here

There's also a kb article on how to install and use the application here

and a blog on how to use it here