Re: [LAU] encryption and performance penalty

From: David Christensen <dpchrist@email-addr-hidden>
Date: Fri Nov 14 2014 - 00:42:20 EET

On 11/13/2014 02:31 AM, Atte wrote:
> I'm thinking about protecting my data with encryption. I know it's a
> complex matter, and very hard (impossible?) to make a system 100%
> protected. And I must admit I don't fully understand the technical
> workings of the various available tools, but I found
> https://wiki.archlinux.org/index.php/disk_encryption.
> Now I'm wondering:
> 1) Can anyone share hands-on experience with a particular strategy, why
> did you choose that particular tool, is it easy to setup and work with
> in every-day use?
> 2) Most importantly: How will the various methods affect my systems
> ability to perform under realtime conditions (jack) including
> reading/writing files from a DAW?
> NB: I'm running debian stable, if it matters...

LUKS, dm-crypt, and the Debian installer make partition-based drive
encryption easy:

     https://en.wikipedia.org/wiki/Dm-crypt

Intel added AES-NI to their CPU's a few years ago, which helps with
encrypted drive performance (and is supported by Wheezy):

     https://en.wikipedia.org/wiki/AES_instruction_set

STFW for benchmarks, I've seen anywhere from 2x to 10x improvement in
encrypted disk performance without AES-NI vs. with AES-NI. It's hard to
isolate -- there are many other significant factors in real systems
doing real work.

My subjective experience with SOHO desktops and servers with respect to
drives is that going from HDD to SSD has the most dramatic impact on
performance. dm-crypt encryption causes a noticeable slow-down on older
machines without AES-NI when launching applications or doing bulk
transfers (half speed?), but it's not a deal-breaker. My Core i7-2600S
system with AES-NI, 8 GB RAM, and encrypted SSD is so much quicker than
everything else that I don't notice. I've done some light music work on
both kinds of machines, and haven't encountered any problems due to
encrypted drive performance.

I suggest that you get yourself a newer SSD and give it a try. :-)

HTH,

David

p.s. The old-fashioned trick of increasing RAM to improve performance is
just as valid today as it ever was. How much RAM do you have in your
machine, what is it's capacity, and how much RAM and swap are in use
when you are doing your heaviest music work?

_______________________________________________
Linux-audio-user mailing list
Linux-audio-user@email-addr-hidden
http://lists.linuxaudio.org/listinfo/linux-audio-user
Received on Fri Nov 14 04:15:02 2014

This archive was generated by hypermail 2.1.8 : Fri Nov 14 2014 - 04:15:02 EET