[luau] processor opinion

[MonMotha]

Randall Oshita wrote:
> Rod!
> 
> Dude the P4s are fast esp. with PC1066, that's 533FSB. Expensive though.
> And not supported by Intel.
> Bandwidth for video and stuff. 
> Get RAID too and stripe ur HDs.
> Go to like www.anandtech.com to see benchmarks using apps you plan to
> use.
> 
> Don't think 64bit Hammer gonna help if your software is not 64bit (I
> could be mistaken??)
> 
> 
> We gotta go ride!
> 
> Thanks.
> Randall 
> 
> 

Ah this is the beauty of opensource software.  Even before the code gets 
rewritten, the compiler already supports x86-64, so a simple recompile 
can get some of the more obvious (to the compiler at least) optimizations.

Even without x86-64 optimizations, the hammers run old 32bit code 
blindingly fast (I believe I saw a 700MHz developer sample clawhammer 
beating a P4 1.4GHz, but of course this is an informal devel test).  I 
was mostly referring to the future capabilities though.

As for RAID stuff, remember you don't need a special RAID controller to 
do RAID.  In fact, the promise and highpoint controllers are just 
UDMA/133 controllers with special firmware to make them LOOK like they 
do raid in hardware (they really do it in software, hence why special 
drivers are needed in linux to do raid, separate from single disk). 
This is especialy evident because the promise UDMA/66 addon controller 
(and I assume the recent ones as the design is still the same) could be 
modified using a few wires and a resistor to do raid.

Anyway, don't bother with a dedicated controller unless you're getting a 
really expensive one (unlikely).  Software raid's cpu usage may be 
higher, but it's often actually faster these days because of the 
extremely overpowered CPU in your system.

Regarding P4s, they're fast with Rambus, but as you point out, Rambus is 
REALLY expensive.  Currently sitting at $56 vs. $77 for 256MB PC2100 DDR 
vs. standard (whatever that is) rambus.  Rambus also gets expensive 
quicker as speeds go up as it's getting less popular.  See Warren's post 
to this regard and also the deceptive business practices that coined the 
term "pulling a rambus" (recently applied to Forgent over the JPEG 
patent nonsense).

Unfortunately, the P4 was designed for rambus.  It expects high 
bandwidth and can tolerate the latency that you get with rambus.  It 
chokes when you start putting the slower DDR on it.  Athlons use DDR 
effectively because they expect very low latency on their memory bus. 
Put rambus on an Athlon and it would choke, that's why you haven't seen 
Athlon boards using rambus (also why no one's made a suitable north bridge).

--MonMotha