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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?

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up vote 3 down vote accepted

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:

  • As long as you still have 10-15% of total free space on your hard disk, Filevault 2 will handle any large VM.
  • But, I've looked up the Intel processors used in the 2010 Macbook air models. Unfortunately, none of them support the accelerated encryption!

    • Because your Macbook Air is not very powerful, I do not recommend using VMs in Filevault 2, or Filevault 2 at all, if you don't really need it.
    • Enabling Filvault 2 will cause large drops in reading/writing speeds to your flash drive without accelerated encryption.

Also see:

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