Service Level Indicator (SLI)

Context:
- It can (typically) be used to monitor and report the performance of a service against agreed Service Level Objective (SLO)s.
- It can (often) include measures such as latency, Throughput, Availability, and error rates.
- It can range from simple measurements like uptime to complex assessments like transaction completion rates within a specified time frame.
- ...
Example(s):
- In a web hosting service, an SLI might be the percentage of time the server is operational (Uptime).
- In a cloud storage service, an SLI could measure data durability, ensuring data is not lost or corrupted.
- In a customer support service, SLIs could include call answer times and first call resolution rates.
- DB Durability in storage systems and end-to-end latency in data processing systems.
- ...
Counter-Example(s):
- SLO, the targets set for SLIs.
- SLA, the comprehensive agreements that include SLOs, among other terms.
See: Durability (Database Systems), Information Technology, Service Level, Service Provider, Service Level Objective, Service Level Agreement, Latency (Engineering), Throughput, Availability.

References

(Wikipedia, 2022) ⇒ https://en.wikipedia.org/wiki/Service_level_indicator Retrieved:2022-6-6.
- In information technology, a service level indicator (SLI) is a measure of the service level provided by a service provider to a customer. SLIs form the basis of service level objectives (SLOs), which in turn form the basis of service level agreements (SLAs);^[1] an SLI is thus also called an SLA metric.
  Though every system is different in the services provided, often common SLIs are used. Common SLIs include latency, throughput, availability, and error rate; others include durability (in storage systems), end-to-end latency (for complex data processing systems, especially pipelines), and correctness.