This topic describes metrics that LaunchDarkly autogenerates from certain OpenTelemetry span events.
LaunchDarkly’s server SDKs support instrumentation for OpenTelemetry traces. Traces provide an overview of how your application handles requests. For example, traces may show that a particular feature flag was evaluated for a particular context as part of a given HTTP request. When LaunchDarkly receives OpenTelemetry trace data containing certain span events, it processes and converts this data into metric events that LaunchDarkly metrics track over time.
There are two types of events that LaunchDarkly creates from OpenTelemetry traces: route-specific events and global events. Route-specific events are useful when you are experimenting with a change that is known to impact a small subset of your server’s HTTP routes. Global events are useful when you believe your change may impact all routes, or when you are not sure of the impact of your change.
To learn more, read OpenTelemetry for server-side SDKs.
Autogenerated OpenTelemetry metric events are prefixed with otel. LaunchDarkly generates the following metrics from the events that LaunchDarkly produces from your OpenTelemetry trace data. This trace data includes the feature flag and the context for which you evaluated the flag. You can also create these metrics manually if you wish.
These expandable sections explain the metrics that LaunchDarkly autogenerates from OpenTelemetry traces:
User HTTP error rate (OpenTelemetry) otel.http.error
Metric kind: Custom conversion binary
Suggested analysis unit: User
Definition:
0Description: Measures the percentage of users that encountered an error inside HTTP spans at least once, as reported by OpenTelemetry. Useful when running a guarded rollout.
Per-route HTTP request errors http.error;method={http.request.method};route={http.route}
Metric kind: Custom conversion binary
Suggested analysis unit: Request
Definition:
0Examples:
http.error;method=GET;route=/api/v2/flagshttp.error;method=PATCH;route=/api/v2/flags/{id}User HTTP 5XX response rate (OpenTelemetry) otel.http.5XX
Metric kind: Custom conversion binary
Suggested analysis unit: User
Definition:
0Description: Measures the percentage of users that encountered an HTTP 5XX response at least once, as reported by OpenTelemetry. Useful when running a guarded rollout.
Per-route HTTP 5XXs (OpenTelemetry) http.5XX;method={http.request.method};route={http.route}
Metric kind: Custom conversion binary
Suggested analysis unit: Request
Definition:
0Examples:
http.5XX;method=GET;route=/api/v2/flagshttp.5XX;method=PATCH;route=/api/v2/flags/{id}User non-HTTP exception rate (OpenTelemetry) otel.exception
Metric kind: Custom conversion binary
Suggested analysis unit: User
Definition:
0Description: Measures the percentage of users that encountered an exception outside of HTTP spans at least once, as reported by OpenTelemetry. Useful when running a guarded rollout.
Average request latency (OpenTelemetry) otel.http.latency
Metric kind: Custom numeric
Suggested analysis unit: Request
Definition:
Description: Measures the average request latency, as reported by OpenTelemetry. Useful when running a guarded rollout. For best results, use a ‘request’ analysis unit and send ‘request’ contexts.
P95 request latency (OpenTelemetry) otel.http.latency
Metric kind: Custom numeric
Suggested analysis unit: Request
Definition:
Description: Measures the 95th percentile request latency, as reported by OpenTelemetry. For many applications, this represents the experience for most requests. You can adjust the percentile to fit your application’s needs. Useful when running a guarded rollout. For best results, use a ‘request’ analysis unit and send ‘request’ contexts.
P99 request latency (OpenTelemetry) otel.http.latency
Metric kind: Custom numeric
Suggested analysis unit: Request
Definition:
Description: Measures the 99th percentile request latency, as reported by OpenTelemetry. For many applications, this represents the worst-case experiences. You can adjust the percentile to fit your application’s needs. Useful when running a guarded rollout. For best results, use a ‘request’ analysis unit and send ‘request’ contexts.
Per-route HTTP request latency (OpenTelemetry) http.latency;method={http.request.method};route={http.route}
Metric kind: Custom numeric
Suggested analysis unit: Request
Definition:
Examples:
http.latency;method=GET;route=/api/v2/flagshttp.latency;method=PATCH;route=/api/v2/flags/{id}