Configuration reference¶

Every Pulse property lives under the pulse.* namespace. As of Pulse 2.0 the surface is split into one @ConfigurationProperties record per feature (CardinalityProperties, TimeoutBudgetProperties, TenantProperties, SloProperties, …) living in each feature's package under io.github.arun0009.pulse. Generated metadata lives in META-INF/spring-configuration-metadata.json (merged with processor output from each *Properties record), so IntelliJ and VS Code autocomplete with type hints out of the box.

See your effective configuration at runtime¶

The single source of truth for "what is actually running" is the actuator:

$ curl -s localhost:8080/actuator/pulse/effective-config | jq

This dumps the resolved pulse.* configuration tree (every per-feature *Properties record merged), so you can see exactly which defaults won and which keys you overrode.

For a browser-friendly view, hit /actuator/pulseui.

A production-shaped baseline¶

Most teams need to override only a handful of keys. Here's the "I-want-to-tune-it-for-prod" minimum:

spring:
  application:
    name: order-service

management:
  tracing:
    sampling:
      probability: 0.10              # 10% in prod, 1.0 in dev — Boot's standard knob
pulse:
  sampling:
    prefer-sampling-on-error: true   # rescue error spans the head sampler would drop
  timeout-budget:
    default-budget: 2s
    maximum-budget: 30s              # edge clamp
    safety-margin: 50ms
  cardinality:
    max-tag-values-per-meter: 1000
  slo:
    objectives:
      - name: orders-availability
        sli: availability
        target: 0.999
  health:
    otel-exporter-stale-after: 5m
  shutdown:
    otel-flush-timeout: 10s

Every subsystem also exposes a single pulse.<subsystem>.enabled toggle so you can disable any feature without exclusions or conditional beans.

Per-subsystem keys¶

Each feature page lists its own configuration prefix, defaults, and gotchas. The high-traffic ones:

Subsystem	Prefix	Key page
Cardinality firewall	`pulse.cardinality`	features/cardinality-firewall.md
Timeout-budget	`pulse.timeout-budget`	features/timeout-budget.md
Trace-context guard	`pulse.trace-guard`	features/trace-context-guard.md
SLO-as-code	`pulse.slo`	features/slo-as-code.md
Sampling	`pulse.sampling`	features/sampling.md
Multi-tenant context	`pulse.tenant`	features/multi-tenant.md
Request priority	`pulse.priority`	features/priority.md
Container memory	`pulse.container-memory`	features/container-memory.md
Kafka time-lag	`pulse.kafka` (`propagation-enabled`, `consumer-time-lag-enabled`)	features/kafka-time-lag.md
Cache (Caffeine)	`pulse.cache.caffeine`	features/cache.md
OpenFeature	`pulse.open-feature`	features/openfeature.md
Shutdown / drain	`pulse.shutdown`	features/graceful-shutdown.md
Health indicators	`pulse.health`	features/actuator.md

Compatibility matrix¶

Component	Supported
Java	21, 25 (CI runs both)
Spring Boot	4.0+
Micrometer	The version Boot 4 brings transitively (no override needed)
OpenTelemetry SDK	The version `io.opentelemetry.instrumentation:opentelemetry-spring-boot-starter` brings
Logging	Log4j2 by default; Logback supported via opt-in
GraalVM native	Reflection / proxy / resource hints registered via `RuntimeHints`; CI runs a native-image smoke workflow (`native-smoke.yml`)

Pulse uses Boot 4's repackaged actuator API, the new Micrometer + OTel starters, and Java 21 records / pattern matching. A Boot 3.x backport is not planned for the 2.x line.

Stability¶

See API stability for the 2.x compatibility promise — what's stable across minor versions, what's internal, and how deprecations land.