Solve Parallels Virtual Machines Mac Sloooowness

Sometimes I need to boot Window on my Mac. I'm using Parallels 7 for booting my BootCamp Windows 7 installation.
I know there's a new version of Parallels, but I'm not buying a new one for now. Did this since version 4, and it seems as if Parallels got slower every version. This could also be the fault of windows.

Booting windows 7 on my parallels machine slowed down my complete Machine drasticly!!
I played with options optimize for Mac, or for Host. No difference.
I trimmed down the looks of my Windows 7, so it looks like pre-XP.
I even blamed Avira Antivirus..

After doing some testing I found out it is not the CPU that's loaded, but the bottleneck seemed to be IO..

Windows Vista and Windows 7 make use of a superfetch function the preloads data in memory smartly when booting the machine. This is NOT what I want on my Virtual Machine!
Please do not use up all my memory...

I found a BIG gain in performance (of My Mac) by disabling the service:

  • Control Panel
  • Administrative Tools
  • Services
  • Stop the service "Superfetch" en set it to Manual
    • This worked great for me!
      (Btw I also disabled the indexing of my complete C drive)