Re: Dragonfly and Hyperthreading....

[Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx>]

:I think .01% is a bit low. But then again, 99.9% of all applications are 
:UP, and no-one seems interested in supporting that market???
:
:I'm most entertained by my customers who buy 3.4Ghz EE CPUS and use
:32-bit/33Mhz NICs in their servers....
:
:Most of the stuff going on now is just plain PR, because as you say, most 
:people don't need more than
:what today's CPUS deliver anyway. I've never seen any compelling evidence
:that AMD-based machines are faster in practice.  Right now I'm testing a 
:3.4/800Ghz P4 system with 1K cache and PCIExpress and its slower than 
:a 3.06/533 Xeon with 512K cache and PCI-X. The faster CPU is faster in raw 
:processing, but the "architecturally slower" machine is faster with larger 
:packets, which should be the opposite.  The truth is that no-one has any 
:idea what they're buying, and you can't even use the "specs" to infer that 
:one machine is faster than another because there are so many external 
:factors.
    
    From the point of view of cpu power per watt AMD wins hands down.  As
    I said, this is becoming the #1 concern for anyone running more then
    a few machines.  Insofar as raw performance goes... well, I think AMD
    is edging-out Intel in most areas these days.  The story the benchmarks
    tell is that the cpus are typically within 15% of each other anyway,
    and Intel can only really win benchmarks that are optimized specifically
    for its cpus or which are FP intensive.  Intel still edges AMD on FP
    performance, but that's about it.  The real problem for Intel is that
    producing on-par performance is costing them 20% more power (or even
    more!), and a lot of additional beefing up of caches, memory subsystems,
    and so forth.  And consumers have started complaining about the fan
    noise.

    Intel has only been able to compete by using innovative technologies
    to reduce the feature size on the wafer and to reduce transitor
    leakage.  What they aren't telling you is that if they did an AMD
    design using their wafer technology the results would blow their own
    cpus away.  AMD has a lot of room to grow into new technologies while
    Intel is forced to use the bleeding edge just to keep up.  What is 
    interesting about this is that IBM has even *better* wafer technologies
    then both Intel and AMD which until recently they have been using only
    for their PowerPC line of cpus.  But now it looks like AMD is going to
    be able to tap into IBMs new fab technologies and that could be a
    serious crimp on Intel once the pipeline catches up.

:My problem is that "2-3 years" is a lifetime, and I have no confidence that 
:things will play out the way we suspect. What to do while Dragonfly and
:FreeBSD are in transition? Retire? Switch to LINUX? Argh!
:
:On a side note, do you see intel moving their Pentium-M technology to
:the "desktop"? My 2.0Ghz P-M notebook kicks butt.

    I don't have any knowledge about Intel's P-M.  Intel has historically
    done a better job at managing notebook power use, but AMD has the 
    better architecture for low power designs and now that they are focusing
    on it I expect them to win that race too, eventually.

					-Matt
					Matthew Dillon 
					<dillon@xxxxxxxxxxxxx>