Pulse/docs/monitoring/PROMETHEUS_METRICS.md

📊 Prometheus Metrics

Pulse exposes metrics at /metrics (default port 9091).

Example scrape target:

• http://127.0.0.1:9091/metrics

This listener is separate from the main UI/API port (7655) and binds to loopback by default. Use PULSE_METRICS_BIND_ADDRESS only when a scraper must reach Pulse from another host.

When PULSE_METRICS_TOKEN is set, Pulse refuses to serve that bearer token on a non-loopback plaintext listener unless PULSE_METRICS_ALLOW_INSECURE_REMOTE=true is explicitly set. Prefer a local Prometheus agent, SSH tunnel, VPN-private scrape path, or TLS/mTLS reverse proxy for remote scraping.

Variable	Description	Default
PULSE_METRICS_PORT	Metrics listener port.	9091
PULSE_METRICS_BIND_ADDRESS	Metrics listener bind address. Keep loopback unless a protected remote scraper needs direct access.	127.0.0.1
PULSE_METRICS_TOKEN	Optional bearer token required for /metrics.	(empty)
PULSE_METRICS_ALLOW_INSECURE_REMOTE	Explicit opt-in to serve PULSE_METRICS_TOKEN on a non-loopback plaintext listener. Use only behind a trusted private network or TLS-terminating proxy.	false

In Docker and Kubernetes you must expose 9091 explicitly if you want to scrape it from outside the container/pod, and the container/pod should set PULSE_METRICS_BIND_ADDRESS to the intended listener address.

Helm note: the current chart exposes only port 7655, so Prometheus scraping requires an additional Service that targets 9091 (and a matching ServiceMonitor).

🌐 HTTP Ingress

Metric	Type	Description
pulse_http_request_duration_seconds	Histogram	Latency buckets by method, route, status.
pulse_http_requests_total	Counter	Total requests by method, route, status.
pulse_http_request_errors_total	Counter	Error totals by method, route, status_class (client_error, server_error, none).

🔄 Polling & Nodes

Metric	Type	Description
pulse_monitor_poll_duration_seconds	Histogram	Per-instance poll latency.
pulse_monitor_poll_total	Counter	Success/error counts per instance (result label).
pulse_monitor_poll_errors_total	Counter	Poll failures by error_type.
pulse_monitor_poll_last_success_timestamp	Gauge	Unix timestamp of last success.
pulse_monitor_poll_staleness_seconds	Gauge	Seconds since last success (-1 if never succeeded).
pulse_monitor_poll_queue_depth	Gauge	Global queue depth.
pulse_monitor_poll_inflight	Gauge	In-flight polls by instance_type.
pulse_monitor_node_poll_duration_seconds	Histogram	Per-node poll latency.
pulse_monitor_node_poll_total	Counter	Success/error counts per node (result label).
pulse_monitor_node_poll_errors_total	Counter	Node poll failures by error_type.
pulse_monitor_node_poll_last_success_timestamp	Gauge	Unix timestamp of last node success.
pulse_monitor_node_poll_staleness_seconds	Gauge	Seconds since last node success (-1 if never succeeded).

🧠 Scheduler Health

Metric	Type	Description
pulse_scheduler_queue_due_soon	Gauge	Tasks due within the next 12 seconds.
pulse_scheduler_queue_depth	Gauge	Queue depth per instance_type.
pulse_scheduler_queue_wait_seconds	Histogram	Wait time between task readiness and execution.
pulse_scheduler_dead_letter_depth	Gauge	DLQ depth by instance_type and instance.
pulse_scheduler_breaker_state	Gauge	0=Closed, 1=Half-Open, 2=Open, -1=Unknown.
pulse_scheduler_breaker_failure_count	Gauge	Consecutive failure count.
pulse_scheduler_breaker_retry_seconds	Gauge	Seconds until next retry allowed.

⚡ Diagnostics Cache

Metric	Type	Description
pulse_diagnostics_cache_hits_total	Counter	Cache hits.
pulse_diagnostics_cache_misses_total	Counter	Cache misses.
pulse_diagnostics_refresh_duration_seconds	Histogram	Refresh latency.

🚨 Alert Lifecycle

Metric	Type	Description
pulse_alerts_active	Gauge	Active alerts by level and type.
pulse_alerts_fired_total	Counter	Total alerts fired by level and type.
pulse_alerts_resolved_total	Counter	Total alerts resolved by type.
pulse_alerts_acknowledged_total	Counter	Total alerts acknowledged.
pulse_alerts_suppressed_total	Counter	Alerts suppressed by reason (quiet_hours, rate_limit, duplicate, etc.).
pulse_alerts_rate_limited_total	Counter	Alerts suppressed due to rate limiting.
pulse_alert_duration_seconds	Histogram	Time from alert fire to resolve (by type).

🚨 Alerting Examples

• High Error Rate: rate(pulse_http_request_errors_total[5m]) > 0.05
• Stale Node: pulse_monitor_node_poll_staleness_seconds > 300
• Breaker Open: pulse_scheduler_breaker_state == 2