Observability lexicon

Every term that comes up when you instrument a system, defined plainly, plus a straight read on what each architecture leaves your team to solve itself. We write these from the engineering side, because they are the definitions we work with when we run observability inside your own cloud.

45 of 45 entries shown

  • AIOps

    AIOps is the application of machine learning and artificial intelligence to IT operations: detecting anomalies, correlating and grouping alerts, suggesting root causes, and increasingly, powering assistants that investigate telemetry conversationally.

  • API

    An API, or application programming interface, is the defined contract through which one piece of software talks to another.

  • APM

    APM, application performance monitoring, is the practice and product category focused on the health of applications in production: request rates, error rates, latency, and the transaction level detail needed to explain them.

  • AWS CloudWatch

    Platform

    Amazon CloudWatch is AWS's built in monitoring service: metrics, logs, alarms, and dashboards, with tracing through X-Ray, integrated by default with nearly every AWS service.

  • BYOC

    BYOC, Bring Your Own Cloud, is a deployment model where a vendor's software runs inside the customer's own cloud account, operated by the vendor but living on infrastructure the customer owns.

  • Cardinality

    Cardinality is the number of distinct values, or distinct value combinations, that an attribute or set of attributes can take.

  • Context propagation

    Context propagation is the OpenTelemetry mechanism that carries trace identifiers and baggage across process boundaries, so that spans created in different services join into a single trace.

  • Counter

    A counter is a metric type for values that only accumulate: requests served, errors thrown, bytes transmitted, jobs completed.

  • Data residency

    Data residency is the question of where data physically lives: which country or region stores it, and where it is processed along the way.

  • Data sovereignty

    Data sovereignty is the question of whose laws govern your data and who can be compelled to grant access to it.

  • Datadog

    Platform

    Datadog is the largest SaaS observability platform, spanning infrastructure monitoring, APM, logs, RUM, security, and dozens of adjacent products, collected largely through its proprietary agent and priced per product.

  • Distributed tracing

    Distributed tracing is the technique of following a request across service boundaries by recording a connected span for each operation it touches.

  • Dynatrace

    Platform

    Dynatrace is an enterprise observability platform known for its OneAgent automatic instrumentation, the Davis AI engine for root cause analysis, and the Grail data lakehouse, sold on a consumption based pricing model.

  • eBPF

    eBPF is a Linux kernel technology that runs small, verified programs inside the kernel itself, attached to events like system calls, network packets, and scheduler activity.

  • Egress costs

    Egress costs are the fees cloud providers charge for data leaving their network, priced per gigabyte and varying by destination.

  • Elastic Observability

    Platform

    Elastic offers observability built on the Elasticsearch stack: log search at its core, with metrics, traces, and APM layered on, available self managed or as the hosted Elastic Cloud.

  • Error budget

    An error budget is the amount of unreliability an SLO permits: one hundred percent minus the target.

  • Gauge

    A gauge is a metric type that records a point in time value that can move in both directions: memory in use, queue depth, active connections, temperature, items in a cart.

  • Grafana

    Platform

    Grafana is the open source standard for dashboards, and Grafana Labs builds an observability stack around it: Loki for logs, Tempo for traces, Mimir for metrics, with Grafana Cloud as the managed offering.

  • Histogram

    A histogram is a metric type that captures how values distribute, by counting observations into buckets, rather than recording what any single value was.

  • Infrastructure monitoring

    Infrastructure monitoring is the practice of tracking the health, performance, and capacity of the layer applications run on: hosts, virtual machines, containers, Kubernetes clusters, and managed cloud services.

  • Instrumentation

    Instrumentation is the code, runtime configuration, or platform setup that makes software emit telemetry.

  • Kubernetes monitoring

    Kubernetes monitoring is observability applied to Kubernetes clusters: the nodes, workloads, pods, and containers that run modern applications, plus the control plane that orchestrates them.

  • Log levels

    A log level is the severity label attached to a log line: DEBUG, INFO, WARN, ERROR, and FATAL in the common scheme.

  • Log management

    Log management is the practice of collecting, processing, storing, and searching log data at scale: every event record your applications and infrastructure emit, made findable when someone needs it.

  • Metric

    A metric is a named numeric measurement tracked over time, request counts, memory usage, response latency, carrying a type, a unit, and attributes that slice it into series.

  • MTTR

    MTTR is mean time to resolution, the average elapsed time from a failure occurring to service being restored.

  • New Relic

    Platform

    New Relic is one of the original APM vendors, now a broad all in one observability SaaS covering APM, infrastructure, logs, browser monitoring, and more, priced on data ingested plus per user seats.

  • Observability

    Observability is the ability to understand what is happening inside a system from the data it emits: its logs, metrics, and traces.

  • Observability pipeline

    An observability pipeline is the layer that moves telemetry from where it is produced to where it is stored, transforming it along the way: parsing, enriching, redacting, filtering, sampling, and routing to one or more destinations.

  • OpenTelemetry

    OpenTelemetry is an open source framework for generating, collecting, and exporting telemetry: the logs, metrics, and traces that describe how software behaves in production.

  • OpenTelemetry Collector

    The OpenTelemetry Collector is a standalone process that receives telemetry from applications and infrastructure, transforms it, and exports it to one or more destinations.

  • OTLP

    OTLP is the OpenTelemetry Protocol, the standard wire format for sending logs, metrics, and traces between the components of an OpenTelemetry pipeline.

  • Real user monitoring (RUM)

    Real user monitoring, RUM, captures what actual users experience in their browsers and mobile apps: page load performance, interaction responsiveness, errors, and the shape of whole sessions.

  • Sampling

    Sampling is the practice of keeping only a subset of telemetry, usually traces, so that volume and cost stay manageable.

  • SDK

    An SDK, or software development kit, is a set of libraries and tools for building against a platform or standard.

  • Semantic conventions

    Semantic conventions are OpenTelemetry's standard vocabulary: the agreed names, types, and values for the attributes that describe telemetry.

  • SLI

    An SLI, service level indicator, is the measurement behind an SLO: the specific, computable signal that stands in for whether users are having a good experience.

  • SLO

    An SLO, service level objective, is a target for how reliable a service should be, expressed as a measured indicator held over a time window: 99.9 percent of requests succeed over 30 days, or 95 percent of checkouts complete in under two seconds.

  • Span

    A span is a single timed operation inside a trace: an HTTP request, a database call, a queue publish, or an internal step worth measuring.

  • Splunk

    Platform

    Splunk is the long standing leader in log analytics and SIEM, acquired by Cisco in 2024, offering log search through its SPL query language plus an observability suite spanning metrics and traces.

  • Tail sampling

    Tail sampling is a sampling strategy that makes the keep or discard decision after a trace completes, when its outcome is known.

  • Telemetry

    Telemetry is the data software and infrastructure emit about their own behavior.

  • Trace

    A trace is the end to end record of one request or workflow as it moves through a system, composed of all the spans that share a single trace ID.

  • Vendor lock-in

    Vendor lock-in is the accumulation of switching costs that makes leaving a platform impractical regardless of how the relationship is going: proprietary instrumentation, captive data, workflows that exist in only one tool, and contracts priced to reward staying.