Definition
Steady State Analysis is the study of a system’s performance after it has moved past its initial transient phase and its operating characteristics have stabilized. It is the primary focus for analyzing nonterminating systems.
Why It Matters
Steady state analysis is the ‘study of the long-term’; it allows engineers to ignore the initial noise of a system’s startup phase and focus on its stabilized, predictable performance, which is the key to designing for durability.
Core Concepts
- Stability: A system is in steady state if its performance measures (e.g., mean queue length) are independent of the starting time of the observation.
- Independence from Initial Conditions: In steady state, the influence of the “empty and idle” starting state has been “washed out.”
- Convergence: The process of reaching steady state. Some systems (e.g., those with arrival rates > service rates) never reach steady state and instead exhibit “explosive” growth.
- Warm-up Period: The time required to reach steady state, which is discarded during analysis.