Signle vs Dual CPUs

[scott_417]

Does the number of CPUs really matters?
I sort of believe larger RAM may be more efficient. Please share your view.


Thanks.

[Steven Clementi · Accepted solution]

Scott:


Performance really depends on how well your application can work with Dual processors. If you are using a program that can only process 1 piece of data at a time, no amount of extra processers will help.


In general, the OS will usually experience better performance with dual processers since it was buit to work with multiple processors. Any application that can benefit from having its data processed 2 pieces or more at a time will also have greater performance.

Having more will usually increase performance across the board since the serverwould have to page less memory to disk in memory intensive data crunching.

The simple answer is yes, The number of CPU's can make a difference, big and/or small.


Steven

[Ivan Ferreira]

The performance of a system is determined by several factors. You cannot tell what to add until you do some performance monitoring.

You first check memory related problems.

Then, verify if the system is cpu bound.

Then, check for I/O problems.

So, to obtain a better performance, severals factors are involved.

[Steven Clementi]

Sorry,

Meant to say that...



Performance derived from having multiple processors really depends on how well your application can work with...

Performance depends on many different factors in Server design, not just the CPU.

;o)

Steven

[Steven Clementi]

Just a sample clipping from the HP High Availability and Clustering Solutions study guide...


"Testing performed by HP has shown that Exchange Server 2003 benefits from
Hyper-Threading technology, with improvements in processor efficiency ranging
from 25% to 40%."


So, even a single Pentium 4 XEON with HT technology performs better than a single processor system. Not sure how much RAM you would need to increase your processor efficiency.

This is not to say that doubling your RAM wouldn't increase the performance of the server by 25 to 40%, each component can offer different performance gains.


Steven