I've encountered sporadic CPU spikes to 100% within my Azure App Service Plan. Oddly, when I delve into the performance of individual App Services within the same time frame, CPU utilization seems within acceptable limits. Additionally, a thorough examination of function calls and SQL queries via both Application Insights and Stackify did not reveal any anomalies during these peak periods.
I'm currently stumped in trying to pinpoint the underlying cause of these CPU spikes. Could anyone offer insights into potential factors contributing to this issue or suggest further diagnostic steps? Any assistance provided would be highly appreciated!
Just because the CPU utilization reaches 100% is not a problem.
If it reaches 100% and starts rejecting requests, then you must dig deeper and worry about it. Otherwise, your Azure App Service Plan is just utilizing the full capacity of vCores that was provisioned by Azure, you need not be concerned for that.
Check your app's AppInsight logs and metrics, for any Http 5xx
errors or any requests queue
getting longer or response time
unusually higher than normal, if none of this happened, and only CPU usage was 100%, then you have nothing to worry about.