Determining cause of CPU spike in azure

Question

I am relatively new to Azure. I have a website that has been running for a couple of months with not too much traffic...when users are on the system, the various dashboard monitors go up and then flat line the rest of the time. This week, the CPU time when way up when there were no requests and data going in or out of the site. Is there a way to determine the cause of this CPU activity when the site is not active? It doesn't make sense to me that I should have CPU activity being assigned to my site when there is to site activity.

Answer 1

If your website has significant processing at application start, it is possible your VM got rebooted or your app pool recycled and your onstart handler got executed again (which would cause CPU to spike without any request). You can analyze this by adding application logs to your Application_Start event (but after initializing trace). There is another comment detailing how to enable logging, but you can also consult this link.