应用程序池标识（.net Framework 4.0）提供响应超时异常，但网络服务（框架2.0）正常运行

Question

We changed framework for our web site from .net 2.0 to 4.0. We had application pool, running under 'network service' for .net 2.0. we are migrating to application pool running under 'Application pool identity' with .net 4.0. Both application pools are in the same server with IIS 7.5.

After migration , we were getting frequent request time out exceptions. Adding the below sections in configuration fixed the issue.

<httpRuntime executionTimeout="600"/> 
<compilation debug="false"/>

Could you please explain the reason for this timeout exception? Why this is now required in .net 4.0 'Application pool identity' ? Why .NET 2.0 'network service' application pool was working without this segment?

Although we had and still exists the below section in configuration

<compilation debug="true" strict="false" explicit="true"> 

we did not have

<httpRuntime executionTimeout="600"/>

Answer 1

'network service' and 'Application pool identity' have completely different rights. Are you sure you are not just hitting a security issue which is taking more time to resolve; you are getting an execution timeout - which means your code is taking way too long to execute. Others have commented on using debug code and that being slower - but this will be minute on a normal HTTP endpoint code. I think the timeout might be occurring because of security negotiation. Try changing your Application Pool identity back to Network Service in IIS Manager and see if your problem goes away.