--- title: Event markers description: Correlate metric changes on APM service pages with the deployments and events that caused them. url: https://coralogix.com/docs/user-guides/apm/features/event-markers/ product: apm feature: APM Overview feature_id: apm-general feature_identifier: apm/apm-general last_updated: '2026-11-09' --- # Event markers When a metric shifts on a service page (error rate climbs, latency drifts, throughput drops) the next question is always "what changed?" Event markers put every dated change on the same timeline as your metrics: deployments, feature-flag changes, incidents, marketing campaigns, or any other event you send to Coralogix. The markers that landed around the shift tell you which change to investigate, on the chart itself, without switching tools. Note Annotations work across APM, Explore, and Custom Dashboards. For the cross-product overview, see [Annotations](https://coralogix.com/docs/user-guides/monitoring-and-insights/annotations.md). ## What you need * Access to APM and the service page for the service you want to analyze. * Event markers ingested through the Coralogix ops-events ingest API. See [Send events to Coralogix](#send-events-to-coralogix). ## Turn on event markers You turn on event markers per service page or from the **Service Catalog**. The setting persists across sessions. 1. In your Coralogix toolbar, select **APM**, then **Service Catalog**. 2. Select the service you want to analyze. 3. In the header at the top of the service page, select the **Chart settings** button next to the time range picker. 4. In the **Chart settings** panel, turn on **Event markers**. [![The Chart settings panel open over the service page, with Event markers turned on, the Service events, Service and related events, and All events options, and the Count restarts toggle below them](/docs/assets/images/event-markers-b96e86615e31da92e175e540e6789058.webp)](https://coralogix.com/docs/assets/images/event-markers-b96e86615e31da92e175e540e6789058.webp) Markers appear as vertical annotations across every chart on the service page, aligned to event timestamps. Hover a marker to see its details, the source system, the event description, and the service and environment it applies to. [![Deployment markers as dashed vertical lines across the service-page charts, with a hover tooltip showing the deployment name, service, and environment](/docs/assets/images/event-markers-live-24b15fa2f839019ed601811573bacae5.webp)](https://coralogix.com/docs/assets/images/event-markers-live-24b15fa2f839019ed601811573bacae5.webp) *Deployment markers line up across every chart on the service page. Hovering a marker shows its details, here, a `product-catalog` deployment to the `otel-demo` environment.* ## Filter which events appear Under **Event markers**, select which markers to show: * **Service events** (default): markers linked to this service. * **Service and related events**: markers linked to this service and its related services. See [Related services](#related-services). * **All events**: every event marker in your account. Events without a `service.name` (for example, account-wide incidents, marketing campaigns, or feature-flag changes) appear only under **All events**, alongside every service's deployment events. Next to **Service and related events**, an **N services** link shows the count of related services included in the filter. Select it to open [Analyze](https://coralogix.com/docs/user-guides/apm/features/analyze.md), where you can inspect the services in the filter. ## Show or hide marker categories On the chart, Coralogix groups markers by category and draws each in its own color, with a matching dashed entry in the chart legend. Deployment events sent as `cdEvent` appear under **Deployments**. Only categories that have events in the current time range appear in the legend. Select a category's legend entry to hide its markers, and select it again to show them. ## Send events to Coralogix Event markers come from the Coralogix ops-events ingest API. For the endpoints, authentication, the full field reference, and the per-platform CI/CD guides, see [Send events to Coralogix](https://coralogix.com/docs/user-guides/monitoring-and-insights/annotations.md#send-events-to-coralogix) in the Annotations guide. ## Related services A related service is a service that sends requests to the current service or receives requests from it. Coralogix derives the set from the [Service Map](https://coralogix.com/docs/user-guides/apm/features/service-map.md). When you select **Service and related events**, the filter includes: * The current service: the service the page is for. * Every service in that service's Service Map neighborhood. ## Limitations * Event markers support two event kinds today: `cdEvent` for continuous-delivery events (with pipeline and VCS metadata) and `customEvent` for generic markers. Both appear on charts; only `cdEvent` carries the CD-specific fields. More structured kinds are added over time. * The **N services** link next to **Service and related events** opens Analyze in a new tab. A later release deep-links directly to the Service Map section within Analyze. ## Related resources * [Service Map](https://coralogix.com/docs/user-guides/apm/features/service-map.md): how Coralogix builds the service dependency graph that defines related services. * [Group by service version](https://coralogix.com/docs/user-guides/apm/features/group-by-service-version.md): compare metrics across the deployments an event marker represents. * [OpenTelemetry CI/CD semantic conventions](https://opentelemetry.io/docs/specs/semconv/registry/attributes/cicd/): the OTel conventions that inspired the `cdEvent` field names.