C4-: Shawn Morel on VMware Fusion
Rougher notes on this one, sorry. It’s dense stuff!
Some things can’t be virtualized: optical drives, graphics cards, etc. This talk mostly about CPU-level stuff.
Hypervisor idea originated at IBM, was formalized by Popek & Goldberg in 1974. Properties of a VMM (virtual machine monitor): equivalence (identical operation to host environment), resource control, efficiency. Formalized set of attributes for a virtualizable processor.
“We don’t call it HijackOSX.kext because Apple wouldn’t like that.” Switching each direction [between host and VM] is 7 microseconds.
VT: Intel’s set of instructions for virtualization; can tell it “trap this instruction for me.” Works fine without it for 32-bit. VMware lives in high memory and protects the VM with segfault protection, which Intel clobbers in 64-bit, necessitating VT.
A lot of the code is cross-platform C and C++. The crux of the code is the Virtual Machine Monitor, which is hard to port to PPC. Porting doesn’t buy you much, since you could only run PPC guest VMs.
3D: working on drivers that will get Aero Glass going. Some Direct X games working without shaders internally. GL coming after that.
“Host doesn’t have to know anything about 64-bit.”
OSx86 + VMware = virtual Mac on Mac right now. VMware would have to implement EFI and Apple’s proprietary ROM.
Snapshot trees? “Want to make things simple for consumers … We can do it, but ought we do it? Do we want Fusion and Workstation on the Mac?”