GELI encryption - CPU requirements?

[RW]

On Wed, 27 May 2009 02:37:08 +0300
Dan Naumov <dan.naumov at gmail.com> wrote:

> Hello (World).
> 
> I am in the process of building a new system for a home NAS/webserver
> use and the hardware is basically this:
> 
> Intel Atom 330 (1,6 Ghz, dualcore), a motherboard based on Intel
> D945GCLF2, 2 GB RAM.
> Silicon Image SIL3124 4xSATA RAID card (intended to be used in JBOD
> mode) 1 x 1.5 TB Western Digital Caviar Green (will get more as the
> need arises)
>
> I have been looking into encrypting most of the system with GELI using
> the default 256bit AES, how big of a performance hit should I expect
> on this CPU? 

Probably quite significant for some disk operations. I have a 4 year
old 2.8 GHz single-core amd64 running i386 and I see ~100% cpu
utilization when copying large files between two geli partitions. If
you haven't already bought it you might want to look at cpus with AES
hardware acceleration.