The :terrain queue at 3 slots/pod was sized for the lightweight per-QSO
TerrainProfileWorker, but RoverPathProfileWorker now runs the full
PathCompute pipeline (terrain + 9 HRRR profiles + sounding + ionosphere
+ scoring + loss + forecast) — same heap profile as :propagation, which
sits at 1 slot precisely to avoid OOM.
A backfill_paths flood today queued ~200 rover-path jobs. With 4 hot
pods × 3 slots, the cluster stacked 15 concurrent path-computes and
two pods OOM-killed in a loop, taking the libcluster ring with them
(visible as the "unable to connect" warnings on the surviving pods).
New :rover_path queue at 1 slot/pod caps cluster-wide concurrency at
(hot_replicas + 1 backfill), drains the existing 200-job backlog
inside ~30 min, and keeps :terrain free for the cheap workers it was
sized for.