Yeah if ESXi was having a problem I would have been sent a PRTG alert and my other guests would also be complaining, but they aren't.

The CPU on my P2Pool barely goes over 270Mhz even though it has 5.3Ghz to play with.
5.3GHz?! What the heck kind of CPU are you running on that monster? Or are you adding up the speeds of multiple cores/processors?