Microsoft Defender gobbling up RAM even when off

[Manmeyco]

Microsoft Defender is right now using over 11 gigabytes of RAM (I have 16). It is unfortunately beating Chrome and Firefox put together. Oh and CPU usage is around 30%.

I tried turning off every setting under "Virus & threat protection settings". I tried adding Defender's own files, and MsMpEng.exe, to the exclusions. I added DisableAntiSpyware to the registry under Windows Defender, tried setting it to 0 and 1.

Nothing is helping, the RAM usage is literally climbing through the roof, to the point where Firefox starts crashing. Is my only solution to use a different antivirus, thereby disabling defender? How can I figure out what is causing it to shoot up?

I'm running on Win10 Pro 20H2.

[Light-Yagami]

Everything that you've done trying to disable it, undo it. Then, update all drivers if you haven't already. Then, do a system-wide antivirus scan and let it to its thing. After that, disable all live file checking and protection. See if problem persists.

 

Maybe another program is triggering Defender to have a memory runaway? With these things, there's sometimes a completely unrelated issue causing all the troubles. Like my laptop touchpad. It starts to lag by 250ms if I have GeForce Experience installed. Windows is weird.

 

I'd start by turning off ethernet, force stopping the defender, restarting the PC and then do what I've described in the first paragraph. 

[Manmeyco]

Thanks for the suggestions. I tried everything you said, but it hasn't helped. When I turn off Real-time protection, CPU usage drops to around 10%, and RAM usage slowly drops to 2gb (from 6, every time I unlock the computer defender is using a different amount, but still a lot), but it doesn't go down to normal levels. When I turn real-time back on, it jumps right back up.

Maybe there's some way to see what it is defender is doing when it's spiking?

[Manmeyco]

Update: CPU has dropped to 0%, ram at 500 mb with Real-time off. Turning real-time on makes it instantly spike back up.

I would rather not leave the antivirus off though (ya know, it's there for a reason...), and anyways real-time turns itself on after a bit. So is my only solution to find a different antivirus to replace defender?