IIS 10 Application Pool CPU Limit and Limit Interval

Question

I have been going over allot of IIS tuning for my web application, and have set everything that I have found online. But I still had some lag after some time idle, even after setting idle time out to 0, and the action to Suspend in the advanced app pool settings. If I also set the CPU Limit to 0, and Limit Interval to 0 - this seems to take care of problem. What would be the drawbacks of doing so, besides no more CPU monitoring. Could this cause other problems? Also it seems strange why if my Limit was 0, and I am experiencing lags on pages left idle, then I set Limit Interval to 0 - problem solved?

Answer 1

Set idle time-out=0 means w3wp.exe keeps running. Disable CPU limit works indicate that recovering from idle still consume CPU usage.

But disable CPU limit is obviously not a good idea, CPU limit protect the operating system from crash. You would rather crash a website but not the entire system. I recommend give it a higher limit.

You can also try to set Start Mode: "always running" in Application pool advance settings to see if it works for you. Another thing to consider is about the session state, which also has an idle time-out configuration. Set a higher value in case this application does a CPU consumption move when lost session state.

At last, you may consider find the reason by using performance profiler in Visual studio.