Identification of the workloads

It is essential that all of the work performed by the system be identified. Especially in LAN-connected systems, a complex set of cross-mounted file systems can easily develop with only informal agreement among the users of the systems. These file systems must be identified and taken into account as part of any tuning activity.

With multiuser workloads, the analyst must quantify both the typical and peak request rates. It is also important to be realistic about the proportion of the time that a user is actually interacting with the terminal.

An important element of this identification stage is determining whether the measurement and tuning activity has to be done on the production system or can be accomplished on another system (or off-shift) with a simulated version of the actual workload. The analyst must weigh the greater authenticity of results from a production environment against the flexibility of the nonproduction environment, where the analyst can perform experiments that risk performance degradation or worse.