[clug] how long to encrypt a 1T exernal disk using LUKS
Daniel Pittman
daniel at rimspace.net
Sun Jun 27 22:22:28 MDT 2010
steve jenkin <sjenkin at canb.auug.org.au> writes:
> jhock wrote on 28/06/10 8:35 AM:
>>
>> I have an eeepc 10HD with Ubuntu 10.0 and Western Digital 1 terabyte
>> external hard disk. I started encrypting the WD disk yesterday using
>> gdecrypt and luks. Does anyone know how long this could take. It is
>> still encrypting this morning. So far top tells me the kcrypt command
>> has been running for "1075:00". I expect that it minutes.
>
> A useful benchmark for crypto performance is ssh/scp.
It is?
> [Which is RSA/DSA to start, then uses lighter symmetric keys, IIRC]
All sane people and protocols do, both because asymmetric encryption is so
slow, and because it is so relatively weak compared to symmetric
encryption.[1]
> I've rarely seen anything that pushes 100Mbps (~10MB/s).
Relatively modest, old hardware can comfortably hit that target; my old core2
2.6GHz system can manage a flat 125 megabytes (yes, *bytes*) a second of
AES-256-IGE 8K blocks, and 138 of AES-256-CBC 8K blocks. On a single core.
> Without evidence/knowledge, I'm going to guess the Atom does crypto like
> a SPARC 300Mhz: ~10Mbps (1MB/sec == 3.5Gb/hour == 200-300 Hrs/Tb)
About one sixth the speed of my core2 machine, IIRC, so around 20MB a second
or so for large-block encryption. Roughly.
Daniel
Footnotes:
[1] See also 1K key lengths being weak in asymmetric encryption now, while
256 bit symmetric keys remain strong.
--
✣ Daniel Pittman ✉ daniel at rimspace.net ☎ +61 401 155 707
♽ made with 100 percent post-consumer electrons
More information about the linux
mailing list