Re: Opteron performance

[Jeroen Demeyer <jdemeyer@cage.ugent.be>]

On Mon, Nov 01, 2004 at 06:30:24PM -0500, Igor Schein wrote:
> Hi,
> 
> I am running Redhat Enterprise AS.  If I link pari against stock GMP
> library, I am losing about 15% performance compared to when I link
> pari against self-built GMP ( same version of GMP in both cases, 4.1.2
> ).  This is a warning to everyone who uses GMP kernel.  
> 
> Any idea on why it may be the case?  I'd like to hear from other
> Opteron users, Redhat and not, whether this result holds.  I know
> Redhat never optimizes its library, but then again I didn't do any
> special optimization when I was building GMP either.

Normally the configuration utility (used by GMP and a lot of other
software) automatically detects the hardware in your system, you don't
have to give it explicitly.  I'm not surprised that there is a 15%
performance difference, I think it's completely normal.

Another question pops up though: how did you measure the speed?


Jeroen Demeyer