OpenTelemetry
https://gyazo.com/c3a5293662d9a3bafef6ff9898624620
OpenCensus と OpenTracing の後繼
specification
OTLP (OpenTeLemetry Protocol)
observability (可觀測性) の三つの道具
tracing
profiling
metrics
logging
$ {\rm logging}_i(t,{\rm tracing_i})={\rm events}(t)*{\rm metrics}_i(t,{\rm tracing_i})?
$ {\rm logging}_{\rm tracing}(t)=({\rm events}*{\rm metrics}_{\rm tracing})(t)?
$ \int_{\rm tracing}{\rm logging}~{\rm d}t={\rm metrics}.
連續$ (f*g)(t):=\int f(\tau)g(t-\tau){\rm d}\tau
離散$ (f*g)(t):=\sum_\tau f(\tau)g(t-\tau)
events
恐らく、統一されてゐる事を確認する、全體的である事を確認する、明晰である事を確認する、と體系化できるのではないか? MELT (metrics, events, logging, tracing)
Event Logs
An event log is an immutable, timestamped record of discrete events that happened over time.
The Anatomy of a Modern Metric
https://www.oreilly.com/library/view/distributed-systems-observability/9781492033431/assets/dsob_0401.png
Tracing
A trace is a collection of spans, which are objects that represent the work being done by individual services or components involved in a request as it flows through a system. A span contains a span context, which is a set of globally unique identifiers that represent the unique request that each span is a part of. Your system may handle dozens, hundreds, thousands, or millions of requests per second – each of these requests would have a single trace identifier, and each span in that request would have a unique span identifier. This span context is immutable and cannot be modified after creation.
Metrics
A metric is some raw measurement about a service, captured at runtime. Logically, the moment of capturing one of these measurements is known as a metric event which consists not only of the measurement itself, but the time that it was captured. These raw measurements are then used by monitoring and alerting systems to provide statistical data about the performance of a service or system.
OpenTracing とは別物だけれど
PrometheusPrometheus.icon text format 0.0.4 が規格に成ったもの