low-latency high-bandwidth OS bypass user-level messaging forcommodity(linux) clusters with commodity NICs(<$200), HELP!(GAMMA/EMP/M-VIA/etc.)

[Patrick Geoffray]

Jon,

On Tue, 2002-12-17 at 02:50, jon wrote:
> Perhaps the P4 isn't that great, but it's an Intel 850E chipset, not
> sure that it sucks :)
> 
> http://usa.asus.com/mb/socket478/p4t533-c/overview.htm is the
> motherboard.
> 

It's a PCI 32/33. Nowadays, you can find plenty of P4-based motherboards
with correct PCI 64/66, for almost the same price.

> Myrinet even says that you can't expect anymore than 100MB/sec-130MB/sec
> out of myrinet on 32-bit 33Mhz with the best chipset.

Well, you cannot expect more than 130 MB/s out of a PCI bus 32 bits/33
MHz. As the PCI is on the path...

> They also say system dependencies can provide latencies from 6.5us to
> 16us.

PCI is one of them.

> Anyways, ya, I don't think any P4 system is a great myrinet host.

The hot machines today are P4-based, using the Serverworks GrandChampion
(GC) or Intel E7500 (Plumas) chipsets. They provide PCI 64/66 (even
PCI-X) and are available from many vendors. All of the Intel i8x0
chipset are just **** regarding PCI performance.

All the machines we bought recently were Supermicro motherboards with
Serverworks GC-LE chipsets. Works great.

Patrick
-- 

Patrick Geoffray, Phd
Myricom, Inc.
http://www.myri.com