ogReliability

ogReliability is a metric used in reliability engineering to quantify the ongoing functional integrity of a system over a defined time horizon. It combines aspects of availability and reliability into a single score to help compare designs, monitor performance, and guide maintenance and deployment decisions.

Calculation: ogReliability can be defined in several formulations. A common additive form uses ogReliability = α · Availability(t) + (1 − α) · Reliability(t), where Availability(t) is the probability the system is operational at time t and Reliability(t) is the probability of no failure up to t. A multiplicative form ogReliability = Availability(t) × Reliability(t) is also used. Some implementations normalize the metric to a 0–1 scale and may include a degradation factor g(t) to account for wear or aging.

Data and interpretation: Estimating ogReliability requires data on uptime, downtime, failure times, repair times, and maintenance events. The horizon t should reflect the intended use case, such as a day, a release cycle, or a service contract period. Higher scores indicate greater expected operational stability; trends over time can reveal improvements or regressions.

Applications and limitations: ogReliability is used in software as a service, embedded systems, and manufacturing to inform release planning, capacity planning, and service-level agreements. Limitations include sensitivity to the chosen horizon, weights, and data quality; the metric can obscure specific failure modes if used in isolation and should be complemented by separate measures of MTBF, MTTR, and defect rates.

See also: reliability, availability, MTBF, MTTR.