Ecto auto-instrumentation created one span per query, so Oban jobs
running thousands of DB ops produced traces with 8k+ child spans.
Tempo's compactor couldn't ingest them — it stalled long enough to
miss heartbeats, got auto-forgotten from the ring, and crash-looped.
The Elixir grpcbox exporter then blew up trying to reconnect.
Stops the cascade: OTLP endpoint removed from prop and prop-backfill
Deployments, opentelemetry_ecto removed from deps, Phoenix/Oban/Bandit
auto-instrumentation retained. Rust workers still export to Tempo.
Adds the OTel deps (opentelemetry + exporter + phoenix / ecto / oban /
bandit auto-instrumentation helpers) and attaches them in
Application.start/2 so the existing Phoenix, Ecto, Oban, and Bandit
telemetry events flow as OTLP spans without any call-site changes.
Exporter config is gated on OTEL_EXPORTER_OTLP_ENDPOINT in
config/runtime.exs — set in the k8s manifests to the cluster
collector (otel-collector.observability.svc.cluster.local:4317).
When unset we switch traces_exporter to :none so nothing is shipped;
dev/test stays quiet.
Resource attributes tag spans with service.name=microwaveprop and
service.namespace=prop, matching the Rust workers' attribute shape
so Tempo can group the full hourly chain across both languages.
Both the main prop deployment and the backfill deployment get the
env; backfill is still a full BEAM node running enrichment workers,
so its Oban/Ecto spans are worth seeing too.
PROP_ROLE=backfill drops the hot-path propagation/commercial/solar
queues and the Cron plugin. Paired with a dedicated Deployment
(nodeSelector: prop-backfill=true, 4Gi memory, no web) this lets 8GB
T620 workers drain the hrrr/weather/terrain/iemre/narr backfill
queues without competing with the hourly grid chain.
