Load Testing & IIS Application pool

If you are doing a load testing to see if load is going to create a crash in your application pool, there is one setting worth checking.
In IIS 7 and 7.5

   Go to Advanced settings for the app pool

   In Rapid Fail Protection,Enable = true, set Maximum Failures=1

In IIS6

   Right click on application pool->Properties

   Click on Health tab

   Enable Rapid fail protection should be checked and change Failures to 1

What this will help you is to catch application pool crash easliy. The default value for failures is 5.Which  means for the first 5 crashes the application pool will recover itself.So  if your goal of testing is to detect crash on load, you might need 5 times load to replicate the issue.