Optimize ASP and IIS by Decoupling Long-running Requests

Optimize ASP and IIS by Decoupling Long-running Requests
Lengthy Web requests, such as those that process and format complex reports, tie up threads from the ASP thread pool. When the number of ASP requests exceeds the number of available threads, you'll see a dramatic slowdown in response time. To solve the problem, you have to make your ASP pages run faster. And to do that you need to decouple the background request processing from the requesting ASP thread.

The ASP Thread Pool
IIS manages the ASP thread pool separately from the ATQ. The IIS metabase property ASPProcessorThreadMax specifies the number of threads per processor allocated for use by ASP. The default value is 25 threads per processor. The default setting allows 25 ASP scripts to execute simultaneously on a single-processor machine, 50 scripts on a dual-processor machine, etc. You can modify this value to allow even more scripts to execute, although Microsoft recommends a maximum value of 100 threads per processor. In my experience, any setting greater than 30-50 threads can begin to cause problems.

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