Workload component identification

Whether the program is new or purchased, small or large, the developers, the installers, and the prospective users have assumptions about the use of the program.

Some of these assumptions may be:

• Who will be using the program
• Situations in which the program will be run
• How often those situations will arise and at what times of the hour, day, month, or year
• Whether those situations will also require additional uses of existing programs
• Which systems the program will run on
• How much data will be handled, and from where
• Whether data created by or for the program will be used in other ways

Unless these ideas are elicited as part of the design process, they will probably be vague, and the programmers will almost certainly have different assumptions than the prospective users. Even in the apparently trivial case in which the programmer is also the user, leaving the assumptions unarticulated makes it impossible to compare design to assumptions in any rigorous way. Worse, it is impossible to identify performance requirements without a complete understanding of the work being performed.