CPU & RAM usage by the Antimalware Service Executable/Windows defender Antivirus Service

Question

Hello,

Is there a way to limit the CPU & RAM used by the Antimalware Service Executable/Windows Defender Antivirus Service.

I saw a CPU Limit which is set to 20 but it has no effect on this service.

2023-07-12_15-02-30 VIPEIVCOR01 Task Manager.jpg

Is it only during the SCANs?

What happen during the Real-Time Protection?

As the service Windows Defender Antivirus Service is continuously running, how to limit its CPU and RAM usage?

Thanks,

Dom

2023-07-12_14-13-33 VIPEIECOR01 CPU Limit.jpg

Answer 1

Hi,

Thank you for posting in Microsoft Q&A forum.

1,Per my experience, the CPU limit setting is not a hard limit but rather a guidance for the scanning engine to not exceed this maximum on average (so the corresponding registry key is named Average CPU Load Factor). The CPU limit setting is used to set the maximum CPU usage for Microsoft Defender for Endpoint scans, but it does not affect real-time protection.

2,You can try to configure Microsoft Defender Antivirus always-on protection settings using Group Policy. To do this, open Local Group Policy Editor, expand the tree to Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus and follow these steps:

Double-click the Allow antimalware service to start up with normal priority policy setting in the details pane on the right and set it to Enabled.

Double-click the Real-time Protection policy setting and configure the policy settings as per your choice.

3,Additionally, you can set limits on the CPU and RAM used by the Microsoft Defender Antivirus Service during scans by using the Set-MpPreference cmdlet. You can set the maximum percentage of CPU usage during a scan by using the "-ScanAvgCPULoadFactor" parameter.

Please refer to:

Set-MpPreference

Thanks for your time. Have a nice day!

Best regards,

Simon

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Answer 2

Hello,

Is there a log which could display what is using (scanned) during this CPU peak?

2023-07-18_9-17-56 OISSANDYMLT.jpg

This peak is almost permanent on laptop... which makes the laptop unusable...

Thanks,
Dom

Answer 3

I have encountered the same problem for the last few months. Makes the laptop unusable so interested in a solution that works.

Pretty appalling that Microsoft themselves create a product that doesn't take into account performance usage.