IIS Hangs on ExecuteRequestHandler

Question

I've encountered a problem with IIS.

The problem is the following:

• Sometimes (intermittent issue) IIS hangs a request in a state called ExecuteRequestHandler, and it spends ~85% of the time.

I couldn't figure out why. Tried everything what I've found in forums, nothing helped. I'm using azure for my backend server and another azure server I have my database.

Can somebody explain what exactly this ExecuteRequestHandler step in a request lifecycle?

I didn't find a good explanation about what this step is doing. Is it executing my code already or is it a pre-task in the lifecycle? The reason I'm asking it to be able to detect where the problem is.

Answer 1

That's when the application code executes.

When it receives a request, IIS creates an IRequest object to represent it, and also creates an IHttpHandler to handle it, the exact class depending on the technology (DefaultHttpHandler, MvcHandler, ...).

There are many steps to completely handle a request, the core one being the HttpApplication.CallHandlerExecutionStep.Execute method calling ProcessRequest on the IHttpHandler.