Technical questions about dual Pentium Chips and Motherboards

[James da Silva]

Context: I am considering embarking on some low-budget, non-commercial, OS
research work using a Dual Pentium system as a base. I have the Intel MP
Spec 1.1 and the Intel book on programming the Pentium, which describe the
APICs and so on. So far, it looks good on paper.

But before I buy, I have some questions:

1. I hear about the P54C/P54CM and P54CT models of the Pentiums. What are
the differences between the models, and which are recommended? Am I
locked in by the motherboard I choose? I presume all these have the
integrated local APICs discussed in the MP spec?

2. One off-hand comment I read recently on the net mentioned SMP-related
problems with some versions of the P54CM and/or some of the current crop
of dual pentium motherboards. Does anyone have any details - like a
step number I should specify to get the fixed part, or which mboards to
stay away from?

3. It seems that (some/most/all?) the current Dual Pentium motherboards
share one L2 cache between the two CPUs (at least the ASUS P54NP4 does).
How can such a system keep up with the processors? Is the cache
hardware on these boards faster than usual, or dual ported or something?

Consider the "perfect" application mix for a 2 CPU system: two CPU bound
user-level processes running which don't share any data, fit in the L2
cache, and don't have any cache line conflicts. Will each program run
as quickly on the dual Pentium CPU as it would on a uniprocessor
Pentium, or will the single L2 cache serialize the cache accesses?

4. I'm interested in any general recommendations of motherboards, and
experiences people have had programming these boards that they would
like to share.

I'll summarize any responses I get to the net.

Thanks,
Jaime
..............................................................................
: James da Silva : UCMP Computer Science Dept. : Faculty Research Asst :
: j...@cs.umd.edu : http://www.cs.umd.edu/~jds : The Maruti Project :

[James da Silva]