Re: Patch: cprng_fast performance - please review.

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Fri, Apr 18, 2014 at 09:54:09PM +0100, Roland C. Dowdeswell wrote:
> On Fri, Apr 18, 2014 at 08:23:11PM +0200, Markku-Juhani Olavi Saarinen wrote:
> >
> 
> > Agreed. AES is worse if you don't have AES-NI.
> > 
> > It has been there on all new systems purchased in some last 3 years,
> > so I would *guess* that it would be > 50% of systems fielded out
> > there.
> 
> It hasn't been there on all new systems purchased in the last 3
> years.  My laptop is about 3 years old and doesn't have AES-NI.
> Neither does my file server (1.5 years old, AMD CPU, IIRC.) nor my
> mobile phone, iPad, last year's MacBook Air, etc.

So, I'm typing this on "last year's MacBook Air".  It does have AES-NI.

Unfortunately, the virtual machines on this laptop that I use for most
NetBSD development don't expose the AES-NI instructions to guests, even
when doing hardware assisted virtualization.  Not RDRAND neither, for
that matter.  And of course, this *is* NetBSD, so assuming all the world's
this year's latest x86 model from a particular manufacturer is not the
greatest idea, either...

Thor