I excluded the follwing folders in windows defender, but the "Antimalware Service executable" is still using a lot of cpu.
C:\Program Files\Android\Android Studio
C:\Users\ME\.android
C:\Users\ME\MyAndroidProjects
C:\Users\ME\AppData\local\Android
Which folder/file did I forget?
This is now described in official documentation:
%USERPROFILE%\.gradle
%USERPROFILE%\AndroidStudioProjects
%USERPROFILE%\AppData\Local\Android\SDK
%LOCALAPPDATA%\Google\<product><version>
Example:
C:\Users\YourUserName\AppData\Local\Google\AndroidStudio4.1