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FileVault: Latency Generator

I’ve been running FileVault on my Retina MacBook Pro since I got it. It’s a screaming fast machine and it leaves my desk in a backpack from time to time. With those two facts, it made sense to turn on FileVault and encrypt my file system so that my data was sure to be secure if my computer ever got stolen.

I’ve since turned it off.

With FileVault on, the Retina MacBook Pro lost what made it feel fast: the instant wake from sleep and the snappiness of some operations. That makes perfect sense, because when data comes off the SSD it needs to be decrypted, and before data is written to disk it needs to be encrypted. That process didn’t take too long with a fast CPU and a speedy SSD, but it added latency. Waking the computer from sleep serves as an example.

Wake with FileVault Off

  1. Log In

Wake with FileVault On

  1. Try to Log In
  2. Wait for keyboard to illuminate
  3. Delete the last half of my password
  4. Log In

That’s no good. Latency frustrates me. In the OS, latency makes the difference between knowing the computer received your instruction and is starting work or wondering if you need to do that again. In the worst case, it makes you stop, think, and compensate.

FileVault is good at what it does, but it (by necessity) adds latency to operations that I do all day long. I’ve decided I’d rather enjoy the computer I purchased than know that no one’s going to get at my files.

Published Oct 8, 2012

Coffee, technology, trees. Written in Vermont.