Metric.msg

Overview

Metric.msg represents a single metric value, optionally labeled, that can be one of three types: counter, gauge, or histogram. It mirrors the metric model used internally by Cartographer’s metrics infrastructure.

Constants

Constant	Value	Meaning
TYPE_COUNTER	0	A monotonically increasing counter.
TYPE_GAUGE	1	A value that can increase and decrease.
TYPE_HISTOGRAM	2	A distribution of values across buckets.

Fields

Field	Type	Description
type	uint8	One of the TYPE_* constants above.
labels	cartographer_ros_msgs/MetricLabel[]	Key/value labels attached to this metric.
value	float64	The metric value, valid for TYPE_COUNTER or TYPE_GAUGE.
counts_by_bucket	cartographer_ros_msgs/HistogramBucket[]	The per-bucket counts, valid for TYPE_HISTOGRAM.

Usage

• For counters and gauges, populate value and leave counts_by_bucket empty.

• For histograms, populate counts_by_bucket; value is unused.

• Metrics are grouped into families via MetricFamily.msg.