amd opteron status re. gmp

Kevin Ryde
Tue, 26 Aug 2003 08:59:19 +1000

Walter Stephan <> writes:
> to run either linux 

Presumably you mean gnu+linux, it's unlikely gmp can do much with only
a kernel.

> (with the integer gmp ops currently being the bottleneck running on an 
> Athlon).

There's some profiler support in the x86 asm code to help you spot
where it's spending time.  The next release will have support for gcc
-finstrument-functions too, for higher resolution.

> Also, does anyone have any idea of a possible timeline for specialized opteron 
> support in gmp?

Torbjorn is hacking at some code right now.  It'll be in the next

> Even if it currently only gives performance equal to the 
> Athlon, if I can count on a significant speedup in a few month's time that 
> could strongly sway me to go for the opteron.

The prospect is for cycle counts roughly the same as athlon, but in
64-bits of course that's 2x as much adding or 4x as much multiplying.

On the whole it looks like a nice chip, but how it works out on the
price versus grunt scale I don't know.