The short version
I think its obvious when I've stopped the windows update service: You can see that right of the cursor that memory usage drops to half of what has been before.
The long version
I think its absolutely not OK that the laptop that has only really low resource using programs running
- browsing 5-10 tabs (no flash)
- vlc playing mp3
- occasionally a git client(tortoisegit)
randomly slows down up to the point that it's completely useless.
When that happens I'm forced to go on a hunt for unnecessary high memory consuming monster apps.
Well most of the time the responsible party is either an antivirus solution that ignores my schedule settings and starts scanning everything it can reach (network shares be prepared :)) OR.. ..svchost.exe..
However one soon realizes that killing that process is a REALLY BAD idea as it manages several services. So its much better to get the process explorer tools from sysinternals and check out which service is the offending one. Or simply open taskmanager and right-click > Jump to services which highlights the services of the memory hungry exe. Finally you can stop the offending service..
That second option granted me the opportunity of the screenshot you can see above..