24/02/2006
Hi
SMP = Symmetric Multiprocessing
The concept is that you can use two processors to process information more quickly.
If you would like an example try installing Red Hat Linux 8.0 or 9 on a dual processor box.
If you have some pentium III processors to use you will need to find a matching motherboard that supports both the physical processor architecture and the processor's core and IO voltage requirements.
The top of the processor is marked showing the speed, voltage, and on chip cache.
Slot one Pentium III processors were a pain because there were Slot one processors with different voltage requirements. eg plugging in a higher speed PIII into a slot one PIII 500 MHz mother board was not generally possible because the motherboards would not supply the correct voltage.
Please don't multiply the processor speed and SMP and equate it to another processor speed. All processors vary in performance according to their architecture, and the architecture of the machine in which they are installed. (Especially the amount of processor onboard cache,
system memory speed, system FSB, etc). In addition there are overheads associated with managing the execution of SMP.
Generally SMP is a good thing. Because it allows an equitable distribution of load across mulpile processors.
However, a single (uni) processor system running at higher
core and IO speeds, together with more on chip cache can often significantly out-perform older dual processor systems with slower processors running an SMP configured OS.
The reality is that if you have obtained multiple PIII CPUs then you need to carefully checkout a motherboard to make sure that it is hardware compatible with the CPUs.
You need to assess the power cost of running the box. Since most multi CPU machines, especially servers, (with the exception of some dual processor desktop motherboards) generally also have a number of power supplies for redundancy (fault tolerance as well as capacity).
In other words it's important to do some homework.
In my experience it is often very tempting to build a
system based on a few valuable parts. However, it is always best to perform a needs analysis first and then determine the costs associated with building a bargin box as opposed to the benefits.
ie. It's not recommended that you buy a Rolls Royce body to fit an acquired Roll Royce engine that you already have, if you can buy a complete Porche for a fraction of the cost complete and ready to drive away.
Unless you particularly need or want a Rolls Royce and are prepared to pay for it.
If you get my drift
Regards
Chris
Hope that helps.
PS. Not all PIII processors will coexist on a dual PIII motherboard.
You will need to access whether you require a matched set.
Sometimes more than the processor speed needs to be identical.
Do a search on the www for processor "stepping".
Here in Victoria Australia a dual PIII server doesn't cost a lot.
In fact there isn't any point building one.
You can often find twin or quad Xeon servers around for very little cost.
Mainly because a fast Uniprocessor machine (P4) has more than enough
horsepower, and no one needs the SCSI bus architecture on these
servers. Another catch is that these older machines often have
SCSI HDD controllers that have been deleted from the Linux SCSI
device drivers in later releases (eg. Fedora, and red Hat Enterprise
Linux)
CGT.
