Observability

Observability

Atmosphere provides built-in support for Micrometer metrics, OpenTelemetry tracing, backpressure management, and cache configuration.

Micrometer Metrics

MeterRegistry registry = new PrometheusMeterRegistry(PrometheusConfig.DEFAULT);
AtmosphereMetrics metrics = AtmosphereMetrics.install(framework, registry);
metrics.instrumentRoomManager(roomManager);

Metric	Type	Description
atmosphere.connections.active	Gauge	Active connections
atmosphere.broadcasters.active	Gauge	Active broadcasters
atmosphere.connections.total	Counter	Total connections opened
atmosphere.messages.broadcast	Counter	Messages broadcast
atmosphere.broadcast.timer	Timer	Broadcast latency
atmosphere.rooms.active	Gauge	Active rooms
atmosphere.rooms.members	Gauge	Members per room (tagged)

With the Spring Boot starter, metrics are auto-configured when micrometer-core and MeterRegistry are on the classpath.

OpenTelemetry Tracing

framework.interceptor(new AtmosphereTracing(GlobalOpenTelemetry.get()));

Creates spans for every request with the following attributes:

Attribute	Description
atmosphere.resource.uuid	Resource UUID
atmosphere.transport	Transport type (WEBSOCKET, SSE, LONG_POLLING)
atmosphere.action	Action result (CONTINUE, SUSPEND, RESUME)
atmosphere.broadcaster	Broadcaster ID
atmosphere.room	Room name (if applicable)

With the Spring Boot starter, tracing is auto-configured when an OpenTelemetry bean is present. Disable with atmosphere.tracing.enabled=false.

MCP Tracing

When atmosphere-mcp is on the classpath, McpTracing adds spans for tool, resource, and prompt invocations:

Attribute	Description
mcp.tool.name	Tool/resource/prompt name
mcp.tool.type	"tool", "resource", or "prompt"
mcp.tool.arg_count	Number of arguments
mcp.tool.error	true if invocation failed

Backpressure

framework.interceptor(new BackpressureInterceptor());

Parameter	Default	Description
org.atmosphere.backpressure.highWaterMark	1000	Max pending messages per client
org.atmosphere.backpressure.policy	drop-oldest	drop-oldest, drop-newest, or disconnect

Cache Configuration

Parameter	Default	Description
org.atmosphere.cache.UUIDBroadcasterCache.maxPerClient	1000	Max cached messages per client
org.atmosphere.cache.UUIDBroadcasterCache.messageTTL	300	Per-message TTL in seconds
org.atmosphere.cache.UUIDBroadcasterCache.maxTotal	100000	Global cache size limit

Samples

• Spring Boot OTel Chat — OpenTelemetry tracing with Jaeger
• Spring Boot Chat — Micrometer metrics and Actuator health

See Also

• Core Runtime
• Spring Boot Integration — auto-configured observability
• MCP Server — MCP tracing