gianm commented on code in PR #18103: URL: https://github.com/apache/druid/pull/18103#discussion_r2155405992
########## docs/configuration/index.md: ########## @@ -2031,6 +1893,155 @@ See [cache configuration](#cache-configuration) for how to configure cache setti |`druid.broker.segment.watchRealtimeTasks`|Boolean|The Broker watches segment announcements from processes that serve segments to build a cache to relate each process to the segments it serves. When `watchRealtimeTasks` is true, the Broker watches for segment announcements from both Historicals and realtime processes. To configure a broker to exclude segments served by realtime processes, set `watchRealtimeTasks` to false. |true| |`druid.broker.segment.awaitInitializationOnStart`|Boolean|Whether the Broker will wait for its view of segments to fully initialize before starting up. If set to 'true', the Broker's HTTP server will not start up, and the Broker will not announce itself as available, until the server view is initialized. See also `druid.sql.planner.awaitInitializationOnStart`, a related setting.|true| +## Metrics monitors + +You can configure Druid services to emit [metrics](../operations/metrics.md) regularly from a number of [monitors](#metrics-monitors-for-each-service) via [emitters](#metrics-emitters). The following table lists general configurations for metrics: + +|Property|Description|Default| +|--------|-----------|-------| +|`druid.monitoring.emissionPeriod`| Frequency that Druid emits metrics.|`PT1M`| +|[`druid.monitoring.monitors`](#metrics-monitors-for-each-service)|Sets list of Druid monitors used by a service.|none (no monitors)| +|[`druid.emitter`](#metrics-emitters)|Setting this value initializes one of the emitter modules.|`noop` (metric emission disabled by default)| + +### Metrics monitors for each service + +:::caution + +Because each monitor is meant for a specific service or services, make sure you configure them for the correct service unless it is meant for any service. For example, if a monitor is meant for the Historical service, configure it in `historical/runtime.properties` rather than `_common/common.runtime.properties`. Review Comment: Yeah, agreed that this cautionary wording is confusing imo. It makes it sound like only the Historical-specific monitors need to be defined in the Historical config file. Actually, the reality is if you use _any_ Historical-specific monitors, then you need to add _all_ the monitors you want to the Historical config file, including the common ones (because the Historical `druid.monitoring.monitors` config overrides the common one, doesn't add to it). IMO, it's best to clarify this, rather than recommending that people always specify monitors in a service-specific way. The main reason is that our out-of-box configurations don't use any service-specific monitors- they have two defined in `druid.monitoring.monitors` in the common properties. The docs should use that as a starting point and then tell people how to think about adding more. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
