Old design fired hourly at HH:25 and built one whole hour of cells
in a single batch. During PSKR peaks (50k+ spots/hour) that batch
held the DB pool long enough to look like a backlog, and a pod
restart between fires lost a full hour because the next cron only
caught the most-recent-prev hour.
- Default window is now current hour + 1 prior. Every 5-min fire
spreads work across the in-flight hour and always covers the
boundary without waiting for the next cron tick.
- lookback_hours arg widens the window for catch-up
(e.g. {"lookback_hours": 24} sweeps the last day after an
outage).
- Unique period 3600 → 240 so consecutive 5-min cron fires actually
slot in.
UPSERT is already idempotent so the ~12 redundant passes per hour
cost only the read+merge. Latency from spot ingestion to sample
creation drops from up-to-60min to ≤5min.
Graham McIntire
b08fc5e449