I'm having the same issue and that flag didn't do anything. This seems to happen every time there is an update to Parallels Tools for me... and to be honest, it's getting annoying having to always debug this product.
The CPU runs excessively high and the disk makes the VM completely unusable (I've had to change my settings to prefer Mac performance over VM just to keep my host running)
**Update: Looking at the Windows VM, Parallels Control Center (prl_cc.exe) is performing 180,000+ I/O reads, the next largest is the runtime broker service at 16,521.
So what exactly is Prl_cc trying to read from the VM disk and WHY??? having an unusable system is not what i'm paying for.
For reference, I have 5 Windows VMs, every one has this issue after the last update.
A temporary fix for this is to disable Windows folder sharing to the Mac. It would appear that the Mac is trying to index the entire guest VM and not doing a very efficient job of it. Adding an exclusion to Spotlight didn't work at all.. so while you lose the ability to transfer files from host to guest, you at least get a working guest.
Last edited: Aug 13, 2016