How do SLIs vary between services?

Service Level Indicators (SLIs) serve as crucial metrics that help organizations assess the performance of their services against defined objectives. The variation of SLIs among services is largely influenced by the specific operational context and requirements unique to each service.

The idea that SLIs differ based on criticality in time and error reflects the fact that different services may have varying performance expectations. For instance, a real-time transaction service may prioritize low latency and high availability as critical metrics, while a batch processing service might focus more on completion time and accuracy. Therefore, the criticality of a service—how important it is for the service to operate effectively within defined parameters—directly impacts the SLIs that are established for it.

In contrast, the other options suggest uniformity or arbitrary determination of SLIs, which does not acknowledge the operational realities faced by different services. SLIs are tailored to reflect the actual needs of the service, ensuring that they are meaningful and actionable in monitoring service performance. This customization allows teams to focus on what truly matters for each specific service, thereby driving improvements and accountability.