Hi, I've built a Mac OS X Yosemite virtual machine in Parallels 10 running on OS X Yosemite host. But the guest VM is slow. Typing in VM is sluggish and opening apps is not responsive. I've allocated 512 MB on VRAM, 4 GB on RAM, 4 vCPUs. I'm running on a MacBook Pro 15 Retina high-end (16 GB RAM, 512 GB SSD). Any tips on getting a more responsive OS X guest ? Thanks !