I am having the same problem (I think). Since upgrading to Parallels Desktop 10 (and I'm running the latest update), on two different Macs running Yosemite, both with Windows 7 Ultimate VMs, my VM drives are exploding in size - without doing anything, they acquire 10+ GB in size very quickly. Using the command above, the size of the disk on the Mac and the Control Panel are the same. However, in the space of two hours, the Local Disk (C) has gone from 65.2 GB to 78 GB. There has been no activity on the VM to create such a massive increase in size. I'm wondering if it's picking up files from OneDrive even though I have turned off the Windows sharing of OneDrive. Hard to explain, but I can say that I've been using Parallels for years and have never experienced this probelm before. If it's not fixed soon, the only option will be a switch to VM Ware, which I'm sure will have it's own set of problems. Please help!!!
Carls-MBP-3:~ CJMMBPRD$ du -sh * /Users/CJMMBPRD/Documents/Parallels/Windows\ 7\ x64.pvm
16K ABBYY
9.2M Applications
24M Applications (Parallels)
5.7M Creative Cloud Files
33M Desktop
198G Documents
24G Downloads
12K Escort
du: Library/Saved Application State/com.adobe.flashplayer.installmanager.savedState: Permission denied
114G Library
255M Movies
101G Music
6.1G OneDrive
30G Pictures
750M Public
78G /Users/CJMMBPRD/Documents/Parallels/Windows 7 x64.pvm
Last edited: Oct 21, 2014