Multiple Processors
With multiple processors, it is reasonable to divide the System: Processor queue by the number of processors. So a twin processor could sustain a queue of 4.
The second rule of thumb is: you are allowed to divide the queue by the number of multiple components. (Processors, Disks or NICs)
As a point of monitoring technique, twin or quad processors give you a chance to compare Processor: %Processor Time Instances, rather than just recording the _Total.
Other Processor counters
1) Process and Thread
If you find a processor bottleneck you can pursue the cause by measuring the Process or even Thread object. What you are looking for is which instance of the Process is responsible for exhausting the processor.
2) System: %Privileged Time and Process: %Privileged Time.
The Windows 2003 operating system can execute, either in Kernel mode, which shows up as %Privileged Time, or User mode which corresponds to %User Time. This means that activities of programs like SQL or Exchange are charged to %User Time.
Here is a combination which would point to an I/O bottleneck, System: %Privileged Time > 20% and PhysicalDisk %Usage > 55%. I
3) DPC
DPC means Deferred procedure calls - The processor is saying 'I am busy I will do this low priority task later.' Processor %DPC Time > 50% is suspicious and may indicate a network card bottleneck.
Solution to processor problems
Getting a second processor will work wonders for servers where the processor is being stressed. Upgrading the processor is another obvious solution for a stressed processor.
When you order the next server consider making it a quad processor. Talking of new kit, when next you spec a new system, consider clustering. Often you need two reasons to break new ground. In addition to the obvious advantage of fault tolerance, clustering can gain extra performance through load balancing across the multiple processors.
No comments:
Post a Comment