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It seems with any version of Windows, including 22H2, a large file read causes 'blips' or interruptions in the user interface interaction due to Windows Defender. It is unclear why Defender cannot use multiprocessing to make this seamlessly?
I have instances of running task manager and doing a large file copy and seeing it drop to ZERO because Defender has to do its thing. How can I make the process act seamlessly and smoothly?
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You will need to analyze what causing the performance issue, there is a PowerShell command known as New-MpPerformanceRecording which you may use. Have a look at:
https://learn.microsoft.com/en-us/microsoft-365/security/defender-endpoint/tune-performance-defender-antivirus
You may open start and search for feedback and open the Feedback Hub app and report this issue.
I know what is causing the performance issue - Defender / mspengine does not work smoothly for large file I/O. I can see it in task manager. Will look at Powershell too. My guess is the correct response would be you have to manual tell Defender not to scan really big files...
Retraction. The issue was not with Defender and large files. The issue was a bit more complicated. Encountered some bizzare behaviour with device hard drive settings and caching. Thank you Reza-Ameri for setting me straight.
Welcome, glad it was helpful.
