Memory Percentage average is above 80 percent for our Website-Live-Plan at 5h in the morning meanwhile 0 request is done!?

Based on the information provided in the context, it is not possible to determine the cause of the high memory usage for your Website-Live-Plan at 5h in the morning with 0 requests. However, it is important to note that high memory usage can impact the performance of your server. You may want to consider monitoring the server's CPU usage and analyzing the traffic patterns to determine the cause of the high memory usage. Additionally, you may want to consider adding faster processors to resolve any bottlenecks caused by high usage rates.

References:

• Monitor CPU Usage
• The Great Skype for Business Memory Mystery

METAIS BASTIEN, Based on my understanding of your issue.

The high memory usage in your Azure app service plan, despite having no requests, could be due to a number of factors. It's important to investigate this issue to ensure it doesn't affect the performance or availability of your application. Here are some steps you can take to troubleshoot the issue:

--If you haven't done this already, to fetch more details about the issue, navigate to your app service - > Diagnose and Solve Problems - review the detector for memory consumption. From there you can better isolate the process consuming the memory if not multiple processes.
Collect memory dump for App Service (Windows)

 --In the left navigation, click on Diagnose and solve problems - Review - “Configuration and Management and “Availability and Performance”  >> “Memory Analysis”

--You may Scale Up or Out - If the memory usage is consistently high, you might need to scale up your plan to a higher tier with more memory or scale out by adding more instances. As a test you any scale-up and late scale-down, as per your requirement.

Additionally,

• Checkout the log directory/location information -here - Access log files
• Enable and review logs to fetch more details about the error

Kindly let us know how it goes, I'll follow-up with you further.

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