The HRDPS pipeline as written was unusable in production: each chain
step took ~5 hours (not 30-90s as the dev-bench claim) because every
`wgrib2 -lon` batch redundantly JPEG2000-decodes ~150 records. With 57
batches × 18 forecast hours, a single cycle would take days to drain.
The /weather Canadian view only needs the current hour, so the cheapest
fix is to stop seeding the rest of the chain entirely:
* Rust grid: HRDPS_STEP=0.5 (was 0.125) drops point count 16× to ~3.5k.
Coarser cells than HRRR, but /weather gets visible Canadian coverage
inside one chain step (~20 min) instead of never.
* GridTaskEnqueuer.seed_current_hour/2 inserts exactly one forecast row
whose valid_time is closest to `now`. fh is clamped to 1..18 so the
Rust F00Reserved branch never fires.
* HrdpsGridWorker switches to seed_current_hour and drops the
6-hour-cycle cron in favor of HH:35 hourly fires. Reseeds are
idempotent on the 4-column unique key.
Also fixes a pre-existing credo "nested too deep" in
ScalarFile.read_point by extracting lookup_in_chunk + hit_or_false
helpers — happened to be on the read path that surfaces this work, so
folding it into the same commit.
Stage 3 (Elixir foundation) of the HRDPS plan. Lands the scaffolding
that lets the Rust prop-grid-rs HRDPS branch be wired up cleanly when
it ships, without further DB or Elixir-side changes.
What ships:
- `grid_tasks.source` column (default 'hrrr', backfill is a no-op).
Replaces the (run_time, forecast_hour, kind) unique index with a
4-column key (..., source) so HRRR and HRDPS analysis/forecast rows
for the same cycle coexist.
- `Grid.hrdps_only_points/0` — Canadian cells inside HRDPS bbox
(49-60°N, -141 to -52°W) but outside HRRR's CONUS bbox. Disjoint
from `conus_points/0` by construction so the two grids never
double-write the same (lat, lon).
- `Grid.point_source/1` — `:hrrr | :hrdps | :neither` classification
for a (lat, lon) pair. Routes per-QSO enrichment to the right NWP
source.
- `GridTaskEnqueuer.seed_with_analysis/2` and `seed/2` accept a
`:source` option; defaults to "hrrr" so existing callers are
unchanged.
- `HrdpsGridWorker` cycle seeder mirroring PropagationGridWorker's
shape but for HRDPS's 4×/day cadence. `:hrdps` queue added to base
Oban config.
What's deferred:
- The Rust `prop-grid-rs` worker doesn't yet branch on
`task.source`. Until that ships, `HrdpsGridWorker` stays out of
runtime.exs cron — it would just produce rows that the Rust worker
mishandles as HRRR. Module doc explicitly notes the dormant state.
- Map overlay extension and FreshnessMonitor HRDPS staleness deferred
to follow-up sessions once real data flows.
Activation path documented in the updated plan file.
Coverage cap recorded as Stage 8 decision: 60°N for v1 (SRTM stops
there). Arctic CDEM deferred to a follow-up plan.
Rust workers (prop-grid-rs) that die mid-claim (SIGKILL, OOM, node
drain) leave grid_tasks rows stuck in status='running' forever,
because claim_next uses FOR UPDATE SKIP LOCKED and nothing resets the
orphan. The /status page then shows a permanent spinner with stale
f00/f10/f18 badges — currently 21 rows claimed as far back as
2026-04-20.
GridTaskEnqueuer.reclaim_stale_running/1 flips rows whose claimed_at
is older than 15 minutes back to 'queued'. Rows that have already
burned through 5 claim/reclaim cycles become 'failed' with a
reclaim-orphan error so the next hourly seed can replace them.
Wired into PropagationGridWorker.seed_chain/0 so it runs every :05
cron tick before new rows are seeded.
Also rename the status panel "Retrying" column to "Failed" — it was
always showing terminal `failed` rows, never retrying ones.
Extracts the memory-hostile HRRR fetch → decode → score pipeline for
forecast hours 1–18 into a separate Rust service (`prop-grid-rs`).
Elixir retains f00 with its native-duct + NEXRAD + commercial-link
enrichment; Rust handles the other 18 steps per hourly chain.
Hand-off via a new `grid_tasks` table (`FOR UPDATE SKIP LOCKED` claim
from Rust, Postgrex `NOTIFY propagation_ready` back to Elixir). Rust
writes the same on-disk score-grid format Elixir already uses, to the
same `/data/scores` NFS tree. Phase 1 ships in shadow mode with
PROP_SCORES_DIR=/data/scores_shadow.
Rust crate layout at `rust/prop_grid_rs/` (1:1 module parity with the
Elixir source it ports):
- grid, region, band_config, scores_file, sounding_params
- scorer: all 10 factors + composite. Matches the Elixir scorer
byte-for-byte across 115 golden-fixture samples (5 scenarios
× 23 bands).
- decoder: wgrib2 subprocess + Fortran-record lola-binary parser
- fetcher: HRRR URL derivation + idx cache (1h TTL) + 8-way
parallel byte-range downloads with 429/5xx retry
- pipeline: end-to-end chain step, f00 rejected at the boundary
- db: sqlx grid_tasks claim/complete + propagation_ready NOTIFY
- bin/worker: tokio main loop, JSON logs, SIGTERM-safe
91 Rust tests + clippy -D warnings clean. 2,158 Elixir tests green.
Elixir additions:
- `GridTaskEnqueuer` seeds fh=1..18 rows from
`PropagationGridWorker.seed_chain/0`
- `NotifyListener` LISTEN → warm `ScoreCache` → PubSub fan-out
- `ShadowComparator` diffs prod vs shadow `.ntms` bodies
- `mix rust.golden` task writes the Rust-side golden fixture
k8s: new `deployment-grid-rs.yaml` pinned to talos5 (32 GB NUC) via
`prop-grid-rs=primary` nodeSelector + `workload=grid-rs:NoSchedule`
toleration, 512 Mi limit, sharing the existing NFS `/data` mount.
The plan document is at `plans/vivid-hatching-quail.md` (local to my
workstation); phases 2 (cutover) and 3 (talos5 concurrency tuning)
follow after 72h of shadow-mode parity.
