Why have my cpu credits suddenly disappeared?

Hello, @James Hicks !

My VM CPU usage has spiked to 100% and now my credits are gone. What happened? If your CPU use has spiked to 100% and the base CPU performance of a Standard_B4ms is 45%, it makes sense that credits would be used up for bursting:

https://learn.microsoft.com/en-us/azure/virtual-machines/b-series-cpu-credit-model/b-series-cpu-credit-model#credits-accumulation-and-consumption

To conduct calculations on credit accumulations and consumptions, customers can utilize the holistic 'credits banked per minute' formula => ((Base CPU performance * number of vCPU) - (Percentage CPU * number of vCPU))/100.

((45% base CPU performance for Standard_B4ms x 4 CPUs) - (100% CPU x 4)) / 100

((45 x 4) - (100 x 4)) / 100

-2.2

If my math is correct here, that would deduct 2.2 credits per VM per minute that it is running at 100% CPU. That's 132 credits an hour and 3,168 credits per day per VM.

What would concern me is if you are seeing a sudden spike in CPU usage and you don't know what the cause is. Have you looked into what is causing the 100% CPU usage?

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Hello Regarding the cpu credits on AVD, try check the information in below link: There are certain VM series, such as B (Burst Mode) Series, that are recommended for quality assurance (QA) and testing. Using these series in the production environment limits the computing capability after the CPU credits are exhausted. To monitor B-series specific credit metrics, you can utilize the Azure monitor data platform Troubleshoot high-CPU issues for Azure virtual machines - Virtual Machines | Microsoft Learn B Series CPU Credit Model - Azure Virtual Machines | Microsoft Learn Also try some methods to check the CPU 100% issue:

1. Since Windows itself needs some background processes to run, many background processes will run on the computer at the same time, and it may cause high CPU usage. Try end the Processes that Cause High CPU Usage.
2. If the CPU usage is very high, and you’re not running any program that would impact it, you can open Task Manager to check it. Search for Services and open. Click Application Management and Restart the service. 3.Viruses on your PC can cause the 100% CPU usage issue, try run windows defender to do a full scan.   Best Regards, Wesley Li ============================================ If the Answer is helpful, please click "Accept Answer" and upvote it.