In the world of automated storage and retrieval systems, like AutoStore, performance measurement is key to ensuring efficiency and reliability. Two critical metrics stand out in this regard: Uptime and System Availability. While related, these metrics offer distinct insights into the operational effectiveness of the AutoStore system. This blog post delves into the nuances of these metrics, explaining their differences, significance, and how they contribute to the overall performance of AutoStore systems.
System Availability is the simpler of the two metrics. It represents the proportion of time the AutoStore system is active and not in a STOPPED mode. For instance, if the system is active for 50 minutes in an hour (60 minutes), its System Availability is approximately 83.4%. This metric is agnostic to the reasons behind the system's inactivity, whether it be maintenance, manual stops, power outages, or robot errors.
Uptime, occasionally referred to as Recovery Uptime, provides a more nuanced view than System Availability. It specifically accounts for system stoppages caused by errors, and the duration of these stoppages is only considered from when the error resolution process begins. For example, if the system encounters a robot error leading to a stoppage of 10 minutes, but the repair process starts 5 minutes after the stop, the Uptime calculation only includes the 5 minutes of active error resolution. In this way, Uptime typically equals or surpasses System Availability, offering a clearer picture of the system's technical reliability.
The rationale for tracking both Uptime and System Availability lies in the different perspectives they provide. Uptime offers insight into the system's technical performance and efficiency in error resolution. It effectively filters out delays attributable to user response times. On the other hand, System Availability sets a fundamental benchmark of the system's operational status, regardless of the nature of stoppages.
The goal for both Uptime and System Availability is ideally 100%, but this is challenging to achieve in practice due to necessary interruptions like software updates and tests. Striving for high values in both metrics is essential, though scenarios with high Uptime but lower System Availability are not uncommon. Such situations are typically temporary and less concerning, like during firmware updates.
In conclusion, both Uptime and System Availability are vital for assessing the performance of AutoStore systems. Understanding the distinction and the role each plays helps in better managing and optimizing these automated systems. Whether you're a technical manager or a business owner, keeping an eye on these metrics can guide you in maintaining high operational standards and ensuring continuous improvement in your AutoStore system.