Re: Byte Addressability And Beyond

Michael S wrote:

On Mon, 3 Jun 2024 08:03:53 -0000 (UTC)
Lawrence D'Oliveiro <ldo@nz.invalid> wrote:
 

On Thu, 30 May 2024 18:31:46 +0000, MitchAlsup1 wrote:
>

30 years ago you could say the same thing about encryption.

>
I don’t think newer CPUs have been optimized for encryption. Instead,
we see newer encryption algorithms (or ways of using them) that work
better on current CPUs.

 I think moderate efficiency on CPU, not too low, but not high either,
is a requirement for (symmetric-key) cipher. Esp. when the key is
128-bit or shorter.

That's correct:
CPU efficiency, primarily on the reference 32-bit platform (PentiumPro 200 MHz) but also on an 8-bit "smart card" implementation was one of the key requirements for the AES competition.
When a group of four programmers (including me) spent a week on CERN's candidate, we were able to triple the speed, bringing it into parity with the eventual winner. All the finalists were more or less the same speed at this point, i.e. able to do full duplex 100 Mbit/s Ethernet traffic (so around 20 MB/s) on a single thread/core.
Terje
--
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"