[Discuss] Full disk encryption

Chris O'Connell omegahalo at gmail.com
Tue Jan 3 12:21:16 EST 2012


That has not been my experience at all.  I have personally encrypted two
machines that had SSD drives, both had modern CPUS, one was an I3 and one
an I7.  There was a substantially noticeable decrease in performance using
TrueCrypt.  In fact, the wait times increased so much after encrypting that
I grew impatient waiting for boot times and Microsoft Office load times.

This article has some scientific testing regarding performance on SSD
drives that are encrypted:
http://media-addicted.de/ssd-and-truecrypt-durability-and-performance-issues/744/




On Tue, Jan 3, 2012 at 12:07 PM, Edward Ned Harvey <blu at nedharvey.com>wrote:

> > From: discuss-bounces+blu=nedharvey.com at blu.org [mailto:discuss-
> > bounces+blu=nedharvey.com at blu.org] On Behalf Of Chris O'Connell
> >
> > ALSO, NO FULL DISK ENCRYPTION should ever be used on an SSD drive.
> >  Performance will drop by 30% and the drive's wear-leveling system and
> > TRIM
> > won't function correctly.
>
> First of all, the supposed 30% performance hit takes you down from 200% to
> 170% performance as compared to an HDD (or whatever arbitrary numbers we
> want to make up for comparing HDD vs SSD performance where SSD performance
> >
> HDD performance).
>
> Second of all, some OSes support TRIM on encrypted drives.  They just
> reduce
> the size of disk they consume by some percentage, and TRIM the unused
> blocks
> as necessary, so there are always some blocks available for use that have
> been TRIM'd.
>
> Third of all, some SSD's support the virtual size reduction as above, but
> do
> it at the hardware level, so there are always TRIM'd blocks available.
>
> In any of the above scenarios, the end result is no significant performance
> degradation on SSD's caused by TRIM vs Encryption.
>
>


-- 
Chris O'Connell
http://outlookoutbox.blogspot.com



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