FileVault taking a full day to encrypt?

[crow]

I just put a new 1TB drive in my MacBook Pro and after running software update I turned on FileVault. It has been encrypting for two hours and currently states it has 16 hours remaining. This seems really wrong to me. Is it because of the size of my new drive? I am using less than 20 GB of the 1 TB right now. I thought turning FileVault on before I added all my data would help the encryption be quicker...

 

[benthewraith]

I just put a new 1TB drive in my MacBook Pro and after running software update I turned on FileVault. It has been encrypting for two hours and currently states it has 16 hours remaining. This seems really wrong to me. Is it because of the size of my new drive? I am using less than 20 GB of the 1 TB right now. I thought turning FileVault on before I added all my data would help the encryption be quicker...

I believe Filevault 2 encrypts the entire volume. It would create an encrypted disk image on the entire hard drive and depending on write speed could take a pretty long time.

 

[Krazy Bill]

Just let it finish. Yes, the initial encryption seems like forever but once it's done you won't notice it during normal use.

 

[Mr. Retrofire]

I believe Filevault 2 encrypts the entire volume.

Right.

It would create an encrypted disk image on the entire hard drive...

No, FileVault2 does not create or use disk images. FileVault2 uses a new, low level API, called CoreStorage. CoreStorage can encrypt data on all block devices like HDDs and SSDs.

From:
http://arstechnica.com/apple/reviews/2011/07/mac-os-x-10-7.ars/13

Lion's FileVault doesn't just encrypt users' home directories, and it doesn't use encrypted disk image files. Instead, it's Apple's implementation of whole disk encryption. This means that every byte of data that makes up the volume is encrypted. Furthermore, this encryption is completely transparent to all software (including the implementation of HFS+ itself) because it takes place at a layer above the volume format—a layer that application software does not see at all.

...and depending on write speed could take a pretty long time.

1 TB (5.200-5.400 rpm) drives have write speeds > 100 MByte/s. The realistic encryption speed on processors which do not support AES-NI, is probably 30-60 MByte/s (Core 2 Duo). Current SB-based MBPs can encrypt 300-400 MByte/s, IIRC (8x-10x faster). So i think, his Mac does not support AES-NI.