Disk encryption


macrumors 6502
Original poster
Sep 14, 2006
Randers, DK
Hi there,

I recently enabled FileVault encryption on my system disk. Took about 6 hours. It's working great.

Then I thought I should encrypt my Time Machine disk as well, so I enabled encryption on it. It seemed it would take a long time, naturally. So then I made a (bad?) decision.. To save time, I thought I would repartition my TM drive, enable encryption on the fresh disk and then start TM from scratch. So I started doing that. But the encryption on the new empty drive seemed to also take a long time. I expected that to be instantaneous, since it was an empty drive, with no data to encrypt.

Is that not how it works? Will drive encryption take a long time, even on an empty drive? My only thought is, that maybe it erases the whole drive, to get rid of potential data, which would make sense. Is that it?

Thanks. :)


macrumors 68020
Jan 21, 2008
Melbourne, FL
I think the problem with your thinking is that it really doesn't encrypt the data, it encrypts the drive--so it takes the same amount of time regardless of how much data is stored on it.