Re: Newb Questions: What does SMP stand for? How do I know if the system is utilizing both CPUs?

From: CL (dnoyeB) Gilbert (CheckMyGPGKey_at_ThisOneIsFake.com)
Date: 07/27/03 

Date: Sun, 27 Jul 2003 00:25:36 -0400

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Mark A wrote:
| "Caught Napping" <your@email.address> wrote in message
| news:pan.2003.07.26.19.08.04.177809@email.address...
|
|>What does SMP stand for? Does this designate the Muti-Processor Kernel.
|>
|>How do you determine if the system is utilizing both CPUs?
|>
|>I'm running a dual PII 450 with Red Hat 9 (and 1/2 gig RAM) and it seems
|>like whenever I fire up an application or two the CPU utilization will get
|>pegged at 50% and the system slows down to a crawl.
|>
|
| Symmetrical Multi-Processing. Just a term for a system that has, and can

symmetric multi processing. Means the processors are symmetric, or the
same.

| effectively use multiple possessors, normally with shared memory and
shared
| disk. Unix/Linux does this very well, but Windows has improved recently in
| this regard.
|

windows (NT) does just fine.

| Clustering is where the processors have their own disk and own memory
| (effectively separate computers with communication between them). Of
course
| one can have clustered SMP systems.
|

yes, now we are talking distributed computing in general.

| When running an SMP system, you need much more memory than would
normally be
| the case because each processor is sharing the total memory. Check
your swap
| activity to see if your system is memory bound.
|
|

~twice as much RAM is a good figure, though slightly overkill if you
have proper SMP chips. The main thing though is processors made for SMP
have bigger caches due to the shared memory factor. You want them
trying to hit RAM much less since its harder to get at it because RAM is
shared.

- --
Respectfully,

CL Gilbert

"Verily, verily, I say unto you, He that entereth not by the door() into
the sheepfold{}, but climbeth up some other *way, the same is a thief
and a robber." John 10:1

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