[Discuss] Full disk encryption

[omegahalo at gmail.com (Chris O'Connell)]

A couple of more supporting links regarding TRIM and wear-leveling (from
Truecrypt):
http://www.truecrypt.org/docs/?s=trim-operation
http://www.truecrypt.org/docs/?s=wear-leveling


On Tue, Jan 3, 2012 at 12:21 PM, Chris O'Connell <omegahalo at gmail.com>wrote:

> 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
>
>


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