November 26, 2008

IT professionals that administer Exchange can feel the burden as the Exchange implementation scales with the company’s email volume and becomes large and complex. By focusing on a few key areas you can improve the performance and availability of Exchange.

MIC

First, as with any performance monitoring exercise, think MIC: Memory - I/O - CPU. When exploring slow downs and problems, first look at memory, then disk I/O, and finally CPU. In the MIC performance formula, memory comes first for a reason. Because Exchange uses a large amount of memory, and memory shortages result in excessive paging (which uses I/O and CPU resources), problems that may appear to be I/O or CPU related may actually be rooted in memory.

There are a few major factors within memory that affect performance. One is kernel memory. Exchange performance can be seriously affected by high usage of kernel memory, which can seriously degrade or off-set Exchange performance if improperly allocated. Other memory problems can be caused by mail queues. For more information on specific ways to control memory on Exchange Server, as well as rules of thumb regarding I/O and CPU, see our Exchange Monitoring White Paper (registration required).