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.
vllm:prefix_cache_hit_rate does not exist in this build; the exported pair is
vllm:prefix_cache_hits_total / vllm:prefix_cache_queries_total, whose rates give
the hit rate. A comment naming a series nobody can query is worse than no
comment.
Neither LLM endpoint was scraped, and frank-medium exports 418 vllm: series —
including the ones this fleet argues about under load: kv_cache_usage_perc (how
full the per-card pool is), prefix_cache_hit_rate (whether pinned conversations
are being reused), num_requests_waiting (queue depth) and the request-latency
histograms. Everything diagnosed tonight by hand — 122,636 KV tokens per card,
thrash when three large contexts overlap, cold-vs-warm prefix reuse — is a
graph now, on the LAN addresses rather than the guarded vhosts.
frank-large comes along in the same change: llama.cpp exposes throughput
counters under llamacpp:, and watching one LLM endpoint without the other was
arbitrary.
The seam added to observability_quadlet.bats pins the cross-file contract that
breaks silently: if a scrape target drifts from the :7770 the units publish,
the graphs vanish with no error anywhere.
- loki: recent releases require compactor.delete_request_store when
retention is enabled (was crash-looping on start)
- prometheus: scrape targets carried legacy dankclaw.local names with
URL schemes (invalid); point at published LAN ports and the gitea
quadlet's published port instead
- grafana: GF_SERVER_ROOT_URL to the canonical HTTPS name
- tests: 3 new seams for the deployed observability configs
Frank