Recipe4.8.Measuring Exchange Performance

Recipe 4.8. Measuring Exchange Performance

Problem

You want to measure and monitor performance of your Exchange servers, comparing current performance against an established baseline.

Solution

Using a graphical user interface

From the Start menu, select Administrative Tools Performance.
Right-click Counter Logs, select New Log Settings, and enter a name for the log. Click OK.
On the General tab, click the Add Counters button and add the performance counters you wish to monitor. Once you've added all the counters you want to be available in this log set, click Close. Change the sample interval time or credentials if desired.
Click the Log Files tab and select the log file type, naming convention, and whether you want to allow log files to be overwritten.
Optionally, click the Configure button and select a log file path and the maximum log file size. Click OK when you're done.
Click OK.

Using the Performance Monitor Wizard

Instead of setting up performance monitoring manually, you can use Microsoft's free Performance Monitor Wizard to quickly configure a set of Exchange-related log settings.

Download and extract the Performance Monitor Wizard (perfwiz.exe) from Microsoft's download site:
http://www.microsoft.com/downloads/details.aspx?FamilyID=31fccd98-c3a1-4644-9622-faa046d69214&DisplayLang=en
From the Start Menu, select Run and enter the full path to perfwiz.exe and click OK.
After the welcome screen, enter the name of the computer that will be collecting the performance monitor logs and click Next.
Select Create New Log and click Next.
Select Standard Perfmon and click Next. (You can select Advanced Configuration to add or remove individual performance counters.)
Enter the name of the computer to be monitored, check the Exchange Server box, and click Next.
Select a name, file size, and location for the performance log file. Check Continue logging in next file to create new log files once the maximum size has been reached, or leave blank to overwrite the file. Click Next.
Either enter the log file's sample interval, or allow the wizard to calculate an appropriate interval for you based upon how much time elapses between significant issues. Click Next.
Press Start to begin running the Performance Monitor log you've just created. Click Next, then click Finish. You can now use the Performance MMC to access the logs.

Discussion

Measurement of Exchange Server system performance monitoring is a discipline that helps throughout the lifecycle of your messaging system. Proper understanding of what affects your system's performance allows you to properly choose the server configuration, watch for problems on an ongoing basis, and solve problems quickly when they occur. It's important to establish a baseline performance log over a meaningful time period when the system is operating normally, so that during routine monitoring you'll quickly notice if something has gone awry. Separate baselines will have to be established for different types of servers in your Exchange organization; obviously an Outlook Web Access front-end server is going to experience different loads than a mailbox server or a connector server.

The Performance Monitor Wizard is a quick way to set up a full set of Exchange performance counters that can then be accessed through the Performance MMC. Exchange bottlenecks will most likely come from your disk subsystem, RAM, processor, or network connection, so these are the performance objects you'll want to give your attention to. You can get a short description of the function of each performance object and counter by clicking the Explain button within the Performance MMC. Microsoft publishes several detailed white papers detailing performance monitoring and tuning for Exchange servers; these are highly recommended as supplemental reading on this topic.

Table 4-4 shows a list of some of the more important performance counters and a description of their function. There are hundreds of performance counters and this represents a fairly generic set; you will want to browse through the performance counters for OMA, public folder stores, POP3, IMAP4, or any other services that need to be measured.

Table 4-4. Exchange-related performance counters
Performance object	Counter	What it does
Logical Disk	% Free Space	Percentage of usable space on the selected logical drive that remains free.
Logical Disk	% Disk Time	Percentage of elapsed time that the selected logical drive was busy servicing read or write requests.
Physical Disk	Disk Reads/secDisk Writes/sec	The rate of read (or write) operations on the physical disk.
Physical Disk	Current Disk Queue Length	Number of requests outstanding on the disk when the performance data is collected.
Memory	Available Bytes (or KBytes or MBytes)	Amount of physical memory available for allocation.
Memory	Pages/sec	Rate at which pages are read from or written to disk.
Network Interface	Bytes Total/sec	Rate at which bytes are sent and received over each network adapter.
Paging File	% Usage	The amount of the page file that is in use, as a percent of the total page file size.
Processor	Interrupts/sec	Rate at which hardware interrupts are serviced by the CPU(s).
Server	Bytes Total/sec	Amount of traffic in bytes sent to and from the network.
Server	Work Item Shortages	Occurs when no work item is available for allocation to incoming service requests.
Server Work Queues	Queue Length	Current length of work queue for the CPU.
System	Processor Queue Length	Number of threads in the processor queue.
MSExchangeIS	Connection Count	Number of client processes connected to the information store.
MSExchangeIS	RPC Operations/sec	Rate at which RPC operations occur.
MSExchangeIS	Write Bytes RPC Clients/sec	Number of RPC bytes written.
MSExchangeIS	RPC Requests	Number of client requests being processed by the information store.
MSExchangeIS Mailbox	Receive Queue Size	Number of messages in mailbox store's receive queue.
MSExchangeIS Mailbox	Send Queue Size	Number of messages in mailbox store's send queue.
SMTP Server	Local Queue Length	Number of messages in the local queue.
SMTP Server	Remote Queue Length	Number of messages in the remote queue.
SMTP Server	Messages Delivered/sec	Rate that messages are being delivered locally.
SMTP Server	Messages Sent/sec	Rate that outbound messages are being sent.
Web Service	ISAPI Extension Requests/sec	Rate at which Internet server API requests are received by the Web service (for OWA).