Dual CPU vs Faster Single

On Sun, 29 Jun 2003 14:35:05 +0200, NM
wrote:

On Sat, 28 Jun 2003 21:44:12 -0400, Keith R. Williams wrote:

...and complicates cross-CPU communications.

Now Felg, please show me that NUMA is *ALWAYS* a win. Sure, NUMA is easy,
but it is here only because it is easy.

It is easier to achieve better performance. Therefore, unless you have
unlimited $$$, NUMA is always a win.

For many (some ?) applications, unless the app(s) is/are very carefully
programmed for NUMA (note AMD calls it SUMO - sufficiently uniform memory
organization), you *could* lose badly with it. Basically if two or more
intensive parallel threads need to share large data structures you're sunk!
I don't think AMD is in a very good position to convince developers to
program specially for Opteron SMP. Let's hope there aren't too many of
those "ill-behaved" apps.

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

On Sun, 29 Jun 2003 20:08:36 -0400, Keith R. Williams wrote:

Whoa! The market for A64 is P4, not Itanic! PLease tell me again how it
will suck! Hell I could say a full-blown Power-5 will blow away any thing
out there, but at what cost? Remember, time is money.

I'm not saying the A64 will suck, I'm saying it would suck as an SMP
processor. It's not designed for this.

In article pan.2003.07.02.14.54.19.266106
@paris.monnet.biz.nospam, am says...
On Sun, 29 Jun 2003 20:08:36 -0400, Keith R. Williams wrote:

Whoa! The market for A64 is P4, not Itanic! PLease tell me again how it
will suck! Hell I could say a full-blown Power-5 will blow away any thing
out there, but at what cost? Remember, time is money.

I'm not saying the A64 will suck, I'm saying it would suck as an SMP
processor. It's not designed for this.

We now understand each other! ;-)

--
Keith