Parallels VM process has high CPU on Macbook Pro Retina when running Chrome in Parallels 8
I had a similar problem in Windows 7 guest OS under Parallels 8. This fixed it:

In Chrome, go to chrome://flags and set 'GPU compositing on all pages' to "Disabled". Restart Chrome

There is a bug report related to this with more details: http://code.google.com/p/chromium/issues/detail?id=172521