Topic Last Modified: 2006-02-13
The Microsoft® Exchange Server Analyzer Tool includes a performance data collection engine that is used to query performance counter objects on computers that are running Exchange 2000 Server or Exchange Server 2003. The performance data collection engine collects data from the %Processor Time (_Total) counter of the Processor performance object to analyze performance data.
This % Processor Time (_Total) performance counter under the Process performance object provides overall utilization of the processors. The average CPU utilization should always be below 80 percent. Higher averages indicate a processor bottleneck. Frequent spikes in processor time above 90 percent also indicate a processor bottleneck.
If the Exchange Server Analyzer determines that a non-Exchange process is using greater than 50% of the total average server CPU time, even if there is no actual processor bottleneck detected, the Exchange Server Analyzer Tool displays a warning.
Removing Potential Processor Bottlenecks
There are many ways to remove potential processor bottlenecks from your Exchange server.
- First, review the applications or tasks that are causing load
on the server. Determine whether the application should be using
the processor time that it is or if there might be an issue with
- If a non-Exchange application is not important to that server,
run that application on another server. If you can do this, move
server roles to other computers also. For example, if the Inetinfo
process is using lots of CPU utilization, consider adding front-end
servers to assume responsibility for the protocol work that
Inetinfo performs. You can also move public folder access to a
dedicated public folder server. Finally, if a server performs lots
of distribution list expansions, you can reduce CPU utilization by
moving distribution list expansion to a dedicated distribution-list
- If you can do this, add more or faster processors to the
server. Also, enable hyper-threading if it is supported by the
processors. You can enable hyper-threading by configuring the
system BIOS. For more information, see the computer manufacturer's
- If increasing the processing power is not a good option, you
must reduce the load on the processors. To reduce the overall
effect on the server, make sure that I/O-intensive, CPU-intensive,
or memory-consuming tasks occur outside ordinary operation
- Make sure that CPU-intensive tasks, such as backup and
maintenance, occur during off-peak hours. Also, make sure that
these tasks are performed in a staged manner. Staging a task means
setting different start times and, preferably, end times for each
task. Staging the maintenance and backup of databases or storage
groups also lessens the effect of these resource-intensive
For More Information
- For more information about Processor Bottlenecks, see Processor
- For more information about Exchange Server performance, see the
Performance and Scalability Guide for Exchange Server 2003
- For more information about troubleshooting Exchange Server
performance issues, see Troubleshooting Microsoft Exchange
Server Performance (http://go.microsoft.com/fwlink/?LinkId=47588).