Thinking about using File Vault 2 on 2010 macbook air. I have a windows 7 virtual machine using vm fusionware that is 13 gb large. What/how will File Vault 2 handle this large space?
Filevault 2 encryption happens on the fly while the system is running.
It does not affect a specific process or application. However, it does affect the I/O performance to the disk. Because Virtual Machines have a lot of read/write operations to the hard drive, the Machine will start slower when loading from the disk.
I have 15GB Virtual Box image for Ubuntu 11.10. It runs very good because my CPU supports the New AES Instructions for accelerated encryption which Filevault 2 makes use of.
In answer to your question: