Windows 10: Windows Defender high CPU consumption

Hello, throughout the past couple months when I am playing a game, I noticed my screen would temporarily freeze/stutter for a second or two. After running some diagnostics, I found that a program MsMpEng.exe was momentarily consuming 100% of my CPU. After working to end/disable the task I found that I need permission from SYSTEM to end Window's Defender. I was wondering if there was any way I could get a walkthrough on how to do this? I have my own anti-malware system in place and do not necessarily need Defender.

:)

 

High CPU usage from Windows Defender

@ignatzatsonic: I am also seeing that file being accessed by the process (not sure it is scanning it, though), but it does not correlate with the elevated CPU usage. This file is more or less accessed by the process all the time, also when it is not consuming CPU.

I haven't seen any serious disk I/O while CPU is consumed, I'd have expected to at least see some high(ish) disk transfer rates if that was the cause, but CPU is consumed while disk transfer by the process is merely a few kB/s, if even that.

It doesn't use a lot of memory either, just 2-300 MB.

Here are screenshots from Process Explorer and Resource Monitor for the process while the CPU consumption is elevated:

 

Windows Defender - high CPU and disk usage

Thank you very much for your quick response. I've taken all steps you suggested. This is the outcome:

• Add a process exclusion
  
  Unfortunately, this didn't work. I added both a path and a process exclusion now.The task scheduler for
• Defender looks like this for me:
  
  
  
  

• It seems no Defender tasks have run since June 30th, yet the process continues to hog the CPU
• I re-ran SFC /scannow. SFC could not find any integrity violations
• I tried disabling behaviour monitoring. The setting did not persist across a reboot, and turning it off did not make a difference while my system was still running.
  
  
  This was the output for Powershell:
  
  

PS C:\Windows\system32> Set-MpPreference -DisableBehaviorMonitoring $True

PS C:\Windows\system32> Get-MpPreference | findstr "Behavior"

DisableBehaviorMonitoring : True

PS C:\Windows\system32>

• Scanning for viruses and leftover antivirus software. This was interesting (yet unfruitful):
  
  Neither Kaspersky nor Emisoft could find any threats. MalwareBytes did find 5 executables in my temp folder, although Virustotal.com reported no danger for the files. This could mean it's a false positive, but I removed all traces of them anyway.
  
  It also found two installers (PUPs) for a Spigot toolbar, I removed those as well. They probably came with some free software package, I try to prevent installing toolbars.
• In installed AVG Anti Virus (the free version). When I rebooted after the installation, Defender was still running and taking up 25-30% of my CPU. I disabled Defender using the Group Policy editor and the service finally stopped.

AVG works for me, but like most free anti virus programs it's full of ads and "free offers" and fishy SSL/TLS interception ("web protection").

I'd like to keep using Windows Defender because it's neatly integrated into Windows 10, doesn't take a lot of resources and doesn't show annoying ads.

I hope anyone can suggest another way to fix this weird Windows Defender problem.

 

Windows 10 Display Blinking with High CPU

After upgrade to Windows 10, experiencing flashing display and high CPU.

• At initial logon screen everything is normal - wall paper and logon screen display with no blinking
• After logon, fan starts as CPU usage spikes, cursor is accompanied by the spinning blue circle
• touchscreen does not respond to swipe to access Recovery/Safe mode for reboot
• able to get to Task Manager and Perfmon to see high CPU usage and explorer.exe is suspended

looking for suggestions on how to either fix or roll back to Windows 8.1