This book presents some examples dealing with performance differences generated on nonoptimal equipment. While the actual numbers themselves aren't terribly interesting, it can be instructive to compare how configuration changes affect sample "before" and "after" data.
Many new features have been added to sendmail in recent releases. The sendmail 8.12 release focused on performance improvements. Anyone running sendmail in a performance-sensitive environment would be well advised to upgrade to at least version 8.12.
Determining appropriate hardware and software configurations to meet a set of email needs is difficult. Creating an appropriate load profile may prove more difficult than setting up the server.
Running a caching-only DNS daemon on a busy email server can be a significant performance win.
