The scraped metrics have no rules over them, so every graph was read after the
fact by a human. This adds shared/prometheus/rules/llm-fleet.yml, loaded via
rule_files and installed by the same copier that ships prometheus.yml (a rule
file nothing loads evaluates nothing, and Prometheus reports no error for it):
LlmKvPoolSaturated kv pool > 90% for 10m — the 122,636-token wall
LlmRequestsQueueing waiting > 0 for 10m — MAXSEQS=4 reached
LlmPrefixCacheCollapse reuse < 20% for 15m with traffic — the thrash signature
LlmEndpointDown scrape target down 2m — both replicas gone
LlmLatencyHigh p95 end-to-end > 60s for 10m — what an operator feels
job:llm_prefix_cache_reuse:rate5m — recording rule shared by the alert and the
dashboard, so the two cannot drift
Every threshold is tied to something measured on this fleet, not to a guess,
and the file says plainly at the top that **nothing is notified**: there is no
Alertmanager here, so a firing alert reaches Prometheus' /alerts page, the
ALERTS metric and the dashboard panel added alongside it — and nowhere else.
Choosing how Frank actually gets paged is his call, not a missing config line.
Seam covers the silent failure mode: rules exist, the config references the
directory, the deployer installs it, and the dashboard graphs ALERTS.
Grafana has been running with zero datasources and zero dashboards, so the
metrics scraped last commit were only reachable through the Prometheus API.
This wires the plumbing and one dashboard, both declared in
shared/grafana/provisioning/ and installed to /opt/grafana/provisioning by the
deployer (the unit already mounted that directory read-only, so nothing about
the container changes):
- datasources/prometheus.yml — Prometheus at http://prometheus:9090, the
container name, not the loopback publish, with a fixed uid so dashboards
reference it without a lookup.
- dashboards/llm-fleet.json — KV pool fill, queue depth, prefix-cache reuse
rate, e2e latency p95, and decode/prefill throughput, with an endpoint
variable covering both frank-medium and frank-large. Every series name was
checked against the live /metrics endpoint: this fleet already shipped one
comment naming a metric that does not exist, and a dashboard full of those
would be worse.
Dashboards stay editable in the UI (allowUiUpdates) because the panels are a
starting point, but the file is the source of truth and the deployer
overwrites Grafana's copy on every deploy.
Planner and seams follow the existing pattern: shared/grafana/** selects the
grafana service, and the tests pin the container-name address plus the
provisioning contract so a rename cannot silently empty the dashboard.
Frank