Reference — Metrics

The console has two distinct metric surfaces: what it emits about itself onto the bus (it is a standard edgecommons component too), and what it consumes and re-serves to the browser (the fleet’s metric class, its main reason for existing). This page covers both, plus the console’s own process vitals, which are a third, browser-only surface that never touches the bus. For the browser-facing wire shapes (MetricSeriesSnapshot, the heartbeat frame’s self object) see data-types.md; for the bus-facing subscription rules see messaging-interface.md.

What the console emits

The console is com.mbreissi.edgecommons.EdgeConsole — a standard edgecommons component with metricEmission.target: messaging (test-configs/config.json) and heartbeat.enabled: true. Like every edgecommons component, its library-owned heartbeat publishes the system-measures metric (sys) on the reserved metric class each heartbeat.intervalSecs tick:

ecv1/{own-device}/edge-console/main/metric/sys

Measure	Unit	Purpose
cpu_usage	Percent	The console process’s own CPU share.
memory_usage	Megabytes	The console process’s own resident memory.
disk_total	Gigabytes	Total disk capacity on the console’s host/volume.
disk_used	Gigabytes	Used disk capacity.
disk_free	Gigabytes	Free disk capacity.
threads	Count	OS thread count of the console process.
files	Count	Open file descriptors (Linux) / open handles.
fds	Count	File descriptors (platform-dependent availability).

This is the same sys metric every edgecommons component emits (library-defined, not console-authored) — it is what makes the console visible in another console’s fleet view, the same way every other component is. The console does not define any metric of its own beyond this standard one; see “The console’s own self-vitals” below for the console’s own-process CPU/memory view, which is a separate, browser-only path.

What the console consumes

Per messaging-interface.md, the console subscribes the fleet-wide metric wildcard (ecv1/+/+/+/metric/#) and keeps a bounded series per (component, instance, metric, measure), capped by component.global.console.metrics (maxSeriesPoints per series, maxSeries overall; overflow is dropped and counted, never evicts existing series). This is the raw feed behind the Metrics screen and the WebSocket metrics/metric frames (data-types.md) — any component’s any named metric, not just sys.

The runtime-attributes projection

Two specific channels are additionally special-cased into a latest-wins RuntimeAttributes projection that feeds the Overview columns and the Component-Detail Health tab (data-types.md):

Channel	Fields folded in
metric/sys	cpuPercent, memoryMb, diskTotalGb, diskUsedGb, diskFreeGb, threads, openFiles, fds — plus a 30-point drop-oldest sparkline ring for cpuPercent/memoryMb
metric/southbound_health	connectionState, readErrors, writeErrors — the southbound adapters’ canonical health metric

Every field is optional: a component that never emitted a measure simply omits it, and the UI shows “—” rather than a fabricated value.

The console’s own self-vitals

Separate from both surfaces above, the console samples its own process CPU% and memory (gateway/src/self_vitals.rs) purely for display in its own browser-facing heartbeat WebSocket frame’s self object (ConsoleSelf) — this is never published to the bus; it powers the Overview “Edge node” tile for the console’s own row, the same way sys powers every other component’s row.

Field	Unit	Purpose
cpuPercent	Percent (one core)	Omitted on the first sample (no baseline yet — never fabricated as 0); present from the second sample onward.
memoryMb	Megabytes	Resident memory of the console process, divided by 1,000,000 bytes.

The same heartbeat frame also carries the console’s own ingress throughput — busMsgsPerSec/busRecentRates, the “Edge bus” tile — sourced from the gateway’s own message counters, not from any UNS metric.

Dimensions

The console’s own emitted metric (sys) carries no dimensions beyond the standard identity (device/component/instance) — it is the library’s system-measures metric, unmodified. The console does not define any dimensioned metric family of its own (it has no southbound signals, polling groups, or command verbs to dimension against); its MetricSeriesSnapshot/MetricSeriesUpdate storage is keyed by (component, instance, metric, measure) for whatever the fleet emits, per data-types.md.