Metrics

This page lists every metric that GET /metrics exposes. The body uses the Prometheus text format. The route listens on server.managementPort when the configuration sets one. Monitoring gives the alerts to build on these metrics.

The test MetricsDocTest compares this page with a live scrape. Every name in the tables must appear in the scrape. Every name in the scrape must appear in a table, or match a prefix of the allowlist at the end of this page.

How the exporter changes a name

The Prometheus exporter renames two kinds of metric:

• It removes the _info suffix. The registered gauge queuebox_info appears as queuebox.
• It adds a second family for a timer. A timer named x_seconds also exposes the gauge x_seconds_max. The gauge holds the largest value of the current decay window.

A counter keeps its _total suffix in the # TYPE line and in the sample line.

QueueBox metrics

Each tag value comes from the configuration or from a fixed set of values, so the number of label sets stays bounded.

Metric	Type	Tags	Meaning
queuebox	gauge	version	The build information. The value is always 1. The registered name is queuebox_info.
queuebox_uptime_seconds	gauge	none	The seconds since the process started.
queuebox_outbox_messages_total	counter	status: sent, failed or dead	The outbox delivery outcomes. A failed outcome is a failed delivery that QueueBox retries.
queuebox_outbox_messages_pending	gauge	none	The outbox messages that wait for a publish.
queuebox_outbox_messages_reclaimed_total	counter	none	The outbox messages that returned to pending after a stale claim.
queuebox_outbox_oldest_pending_age_seconds	gauge	none	The age in seconds of the oldest outbox row in state pending. The value is zero when no row is pending. A count of pending rows cannot separate a busy relay from a dead one, so this is the metric to alert on. The poller refreshes the value at most once per outbox.pendingGaugeIntervalMs, so the value can be up to that interval old. The gauge does not run a query on each scrape.
queuebox_claims_lost_total	counter	component	The terminal writes that lost the claim. Another replica owned the message.
queuebox_outbox_process_errors_total	counter	none	The errors that stopped the processing of one outbox message.
queuebox_outbox_processing_duration_seconds	summary	none	The time to process one outbox message. The summary carries the 50th, 95th and 99th percentile.
queuebox_outbox_processing_duration_seconds_max	gauge	none	The largest processing time of the current window.
queuebox_outbox_publish_duration_seconds	summary	destination_type	The time to publish one message to a destination type, for example http.
queuebox_outbox_publish_duration_seconds_max	gauge	destination_type	The largest publish time of the current window.
queuebox_outbox_destination_messages_total	counter	destination, outcome = success or failure	The outbox messages per destination and outcome.
queuebox_outbox_queue_depth	gauge	destination	The messages that wait for a publish to one destination.
queuebox_http_publish_responses_total	counter	status_class = 1xx, 2xx, 3xx, 4xx, 5xx or other	The HTTP publish responses per status class. A raw status code is never a label.
queuebox_transform_failures_total	counter	strategy	The transform failures per error strategy.
queuebox_inbox_messages_total	counter	status = new, forwarded or duplicate	The inbox messages per status.
queuebox_inbox_relay_errors_total	counter	none	The errors of the inbox relay.
queuebox_inbox_rejections_total	counter	reason = extraction_failed, transform_failed or storage_failed	The inbox messages that QueueBox rejected, per reason.
queuebox_inbox_filtered_total	counter	source	The inbox messages that the header filter of a source dropped. QueueBox stores no row for them. The counter appears after the first drop of a source.
queuebox_inbox_oldest_pending_age_seconds	gauge	none	The age in seconds of the oldest inbox row in state pending. The value is zero when no row is pending. A count of pending rows cannot separate a busy relay from a dead one, so this is the metric to alert on. The relay refreshes the value at most once per inbox.relay.pendingGaugeIntervalMs, so the value can be up to that interval old. The gauge does not run a query on each scrape.
queuebox_cleanup_messages_deleted_total	counter	table	The rows that the retention cleanup deleted, per table.
queuebox_cleanup_duration_seconds	summary	table	The time of one cleanup run, per table.
queuebox_cleanup_duration_seconds_max	gauge	table	The longest cleanup run of the current window.
queuebox_cleanup_last_run_timestamp	gauge	table	The Unix time in seconds of the last cleanup run.

A metric with a tag registers on its first use. A destination that never received a message has no sample until its first publish.

HikariCP pool metrics

DatabaseFactory gives the meter registry to HikariCP through MicrometerMetricsTrackerFactory. Every metric below carries the tag pool, which holds the pool name.

Metric	Type	Tags	Meaning
hikaricp_connections	gauge	pool	The connections in the pool, both idle and active.
hikaricp_connections_active	gauge	pool	The connections that a caller holds.
hikaricp_connections_idle	gauge	pool	The connections that are free.
hikaricp_connections_pending	gauge	pool	The threads that wait for a connection.
hikaricp_connections_min	gauge	pool	The minimum idle connection count of the pool configuration.
hikaricp_connections_max	gauge	pool	The maximum pool size of the pool configuration.
hikaricp_connections_timeout_total	counter	pool	The connection requests that timed out.
hikaricp_connections_acquire_seconds	summary	pool	The time to acquire a connection from the pool.
hikaricp_connections_acquire_seconds_max	gauge	pool	The longest acquire time of the current window.
hikaricp_connections_creation_seconds	summary	pool	The time to create a physical connection.
hikaricp_connections_creation_seconds_max	gauge	pool	The longest creation time of the current window.
hikaricp_connections_usage_seconds	summary	pool	The time a caller held a connection.
hikaricp_connections_usage_seconds_max	gauge	pool	The longest usage time of the current window.

JVM metrics

QueueBox binds no JVM metrics. No jvm_, process_ or system_ family appears in the scrape, because the application registers no Micrometer JVM binder. Read the heap, the thread count and the garbage collection from another exporter.

Do not add a JVM family to this page before a binder exists. MetricsDocTest fails on a documented metric that the scrape does not carry.

Allowlist

The allowlist names the prefixes that this page does not list one by one. It is empty. Every metric of the scrape has its own row above.