There are many changes that can be made that will affect the performance of an email processing server. Making unstructured changes may improve the performance, but applying a methodology will allow the impact of changes to be measured and maximize performance in a shorter time frame.
1. Define performance parameters: Without defining what is to be improved, the process of improving performance can never finish. Parameters that might be chosen include the length of time taken to process an email, the maximum CPU load on the server, the number of concurrent emails to be handled, the success rate of spam filtering, and so on. The choice of parameters and their values should be specific to the site.
2. Measure the current performance: Tools may exist, or may have to be written, to assist in this. Parsing of system logs will give information on times to process emails, from receipt to delivery. Tools such as
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allow measurement of disk I/O and CPU usage....