MSMQ independent clients and servers with multiple physical disks can improve their messaging performance by storing the various files used to implement messaging across multiple physical disks. MSMQ can use up to three different drives to implement message queuing. Folders on the different drives are used to store the message files (.mq files), message logger files, and the transaction logger files.
If you have only two disk drives, put the messaging files on one drive and the message logger and transaction logger files on the other drive.
For optimal transactional performance, put the MSMQ message files, message logger files, and the transaction logger files on three different drives, and put the data and log files for the application you are transacting with on two or more different drives.
Adding additional disk drives ensures that disk access has a minimal impact on messaging performance. However, if you CPU usage is at or near 100 percent, adding additional disk drives will not improve messaging performance. To determine if your computers are limited by disk access or processing power, use Performance Monitor to track the % Processor Time and Avg. Disk Queue Length counters. If sustained CPU use is above 75% while sending messages, adding additional processing capacity may improve messaging performance. If the average disk queue length for any drive is greater than 0.6 while sending messages, additional drives may improve messaging performance.