Performance monitoring is a subject that is discussed frequently in IT departments. It is discussed before servers and applications are purchased, it is discussed while the servers are in the pre-production phase and it is discussed many times after the servers have gone into production.

If the server crashes then forensic analysis is performed to pinpoint the cause of the crash. Sometimes the cause of the crash can be traced back to the exhaustion of resources. But hopefully, with diligent monitoring of the server performance, those scenarios can be detected early as resource consumption ramps up the curve of utilization over time.

Luckily for administrators of Exchange Server there are many tools to help with the monitoring of Exchange Server.

In Doug Gowan’s blog, he has written a very informative guide to monitoring performance of the Exchange Server and has given an excellent overview of what components to monitor. In his blog, Doug discusses such components of the Exchange Server as: RPC operations, DSAccess, memory usage, disk usage and processor utilization.

Memory, disk I/O and processor utilization are the obvious server components to monitor for any application in a production and non-production environment. How an IT department responds to the lack of resources will differ based on the priorities of the applications and more importantly on the budget that is allocated for capital expenditures.

If the server is lacking in memory then the most often knee-jerk reaction is to simply buy more memory. But with Exchange Server there are tuning parameters which can be adjusted to optimize the amount of memory that is needed by the server. Ideally, these adjustments will result in less memory usage by the Exchange Server.

When the store process of Exchange Server 2003 is started, Exchange Server will perform an optimal memory configuration check. If the memory settings are not optimal then an event 9665 is logged in Event Viewer.

This 9665 error can happen for multiple reasons such as:

• The SystemPages value in the registry is set outside the range of 24000 to 31000.
• The server is running Windows 2000 and has 1GB or more of physical memory, but does not have the /3GB switch set in the boot.ini file.
• The server is running Windows Server 2003 and has 1GB or more of physical memory and the /3GB switch is set but the /USERVA setting is not listed in the boot.ini file.

The /3GB switch can be added to the Boot.ini file on the server when the Exchange Server 2003 system has 1GB of memory or more installed and contains mailboxes or public folders. However, it is recommended that administrators do not add the /3GB switch when the systems do not contain any mailboxes or public folders.

Adding or removing the /3GB switch is just one step in the process of tuning Exchange Server for best performance. But keep in mind that with Exchange Server 2003 and the /3GB switch that as the utilization is increased then the efficiency of Exchange Server decreases particularly on systems with more than 4GB. This is due to the fact that Exchange Server 2003 does not support instancing, Physical Address Extension (PAE), or Address Windowing Extensions (AWE). It hits its efficiency limit around the 4GB mark.

There is a lot more to discuss about memory usage of Exchange Server systems and in future blog posts I will discuss other tuning configuration setting opportunities.

With respect to monitoring tools Doug does discuss running Performance Monitor on your Exchange Server to collect statistics on the various Exchange Server components installed on the system.

But other tools that administrators should become familiar with include:

• Exchange Server Profile Analyzer - This tool can be used to collect data about server performance, mailbox storage, user access and mail message routing.
• Load Generator Tool which can be used to test the sending and receiving of email messages (MAPI, OWA, ActiveSync, IMAP, POP, SMTP) to Exchange Server. It can also be used to simulate the load generated by some number of users and email messages.
• JetStress tool which can run performance tests against Exchange Server to test the database and log file loads produced by a specific number of users against Exchange.

Doug has also included a link to an Exchange Server performance monitoring document entitled ‘Troubleshooting Microsoft Exchange Server Performance‘. Administrators who wish to dig deeper into the subject of performance monitoring for Exchange Server will find the document most valuable.