ClusterMetrics

Standard metric definitions used by the unstable cluster runtime. The gauges track runner-local entities, singleton processes, registered runners, healthy runners, and acquired shards.

This module only defines the metric handles. The runtime components that manage entities, runners, singletons, and sharding update these gauges while the cluster is running.

5 exports Added in v4.0.0 Source

Metrics

entities

Added in v4.0.0 Source

Creates a gauge tracking the number of active entity instances for each entity type on the current runner.

When to use

Use when instrumenting runner-local entity counts and tagging them by entity type for cluster dashboards.

Details

Bigint gauge named effect_cluster_entities, updated with the entity type as a metric tag.

Gotchas

This gauge is runner-local and sampled by the entity manager loop. Aggregate across runners and expect up to roughly one polling interval of lag.

See

singletons for singleton process counts on the current runner
shards for shard ownership on the current runner

Signature

declare const entities: Gauge<bigint>;

runners

Added in v4.0.0 Source

Represents a gauge tracking the number of registered cluster runners.

When to use

Use to monitor the registered runners currently known to the cluster runtime.

Gotchas

The value can lag briefly during membership changes or failure detection.

See

runnersHealthy for the healthy-runner subset

Signature

declare const runners: Gauge<bigint>;

runnersHealthy

Added in v4.0.0 Source

Represents a gauge tracking the number of cluster runners currently considered healthy.

When to use

Use to monitor the healthy subset of registered cluster runners.

Details

Bigint gauge named effect_cluster_runners_healthy.

Gotchas

The value reflects the runtime's health-check view and can lag during membership changes or failure detection.

See

runners for the total registered-runner gauge

Signature

declare const runnersHealthy: Gauge<bigint>;

shards

Added in v4.0.0 Source

Represents a gauge tracking the number of shards currently acquired by the current runner.

When to use

Use to observe shard ownership held by the current runner during startup, rebalancing, or failover.

Details

Bigint gauge named effect_cluster_shards, updated from the sharding acquisition loop using the current acquired shard count.

Gotchas

This is runner-local, not a cluster-wide shard total. Aggregate per-runner values carefully.

Signature

declare const shards: Gauge<bigint>;

singletons

Added in v4.0.0 Source

Creates a gauge tracking the number of singleton processes currently running on the current runner.

Signature

declare const singletons: Gauge<bigint>;