test: database growth + load-time soak

.github/workflows/soak.yml

@@ -0,0 +1,68 @@
+name: soak
+
+# Database growth + load-time soak (test/db_growth_soak_test.dart). Too slow
+# for every PR — a simulated day costs ~15-30 s through the real ingest — so it
+# runs nightly and on demand, and the per-day size report is kept as an
+# artifact either way.
+on:
+  schedule:
+    - cron: '30 2 * * *'
+  workflow_dispatch:
+    inputs:
+      days:
+        description: Live days to simulate
+        default: '30'
+      history:
+        description: History lengths (days) to time loads at
+        default: '30,180,365,730'
+
+# Per event, so a manual run never cancels the nightly one before its report
+# is uploaded.
+concurrency:
+  group: soak-${{ github.ref }}-${{ github.event_name }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+
+jobs:
+  soak:
+    runs-on: ubuntu-latest
+    timeout-minutes: 120
+    strategy:
+      fail-fast: false
+      matrix:
+        device: [gen4, mg]
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+
+      # Same pin as test.yml, for the same reasons.
+      - uses: subosito/flutter-action@v2
+        with:
+          flutter-version: 3.41.6
+          channel: stable
+          cache: true
+
+      - name: Guard — the lock pins sibling commits, and the pins aren't stale
+        run: bash .github/scripts/check_sibling_pins.sh
+
+      - name: Install dependencies
+        run: flutter pub get
+
+      - name: Soak (${{ matrix.device }})
+        env:
+          OPENSTRAP_SOAK: '1'
+          SOAK_DEVICE: ${{ matrix.device }}
+          SOAK_DAYS: ${{ inputs.days || '30' }}
+          SOAK_HISTORY: ${{ inputs.history || '30,180,365,730' }}
+        run: flutter test --concurrency=1 --reporter=expanded test/db_growth_soak_test.dart
+
+      - name: Keep the size report
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: db-growth-${{ matrix.device }}
+          path: build/soak/db_growth.csv
+          if-no-files-found: ignore

lib/data/db.dart

@@ -9619,11 +9619,21 @@ class LocalDb {
   /// THIS rather than writing its own `MAX(algo_version)` — the pattern had
   /// already reappeared at five readers and two views, and the ceiling has to
   /// be on all of them or it is on none of them.
-  static const String _servedDayJoin =
-      'JOIN (SELECT day_id, MAX(algo_version) AS v FROM day_result '
-      'WHERE algo_version <= $_servedAlgoCeiling GROUP BY day_id) m '
+  static const String _servedDayJoin = 'JOIN ($_servedVersions) m $_servedOn';
+  static const String _servedVersions =
+      'SELECT day_id, MAX(algo_version) AS v FROM day_result '
+      'WHERE algo_version <= $_servedAlgoCeiling GROUP BY day_id';
+  static const String _servedOn =
       'ON r.day_id = m.day_id AND r.algo_version = m.v';
 
+  /// [_servedDayJoin] for the newest N days only (bind N). A LIMIT on the
+  /// outer query comes after the join and its sort, so SQLite fetched and
+  /// sorted EVERY day's row, bundle and all, to return N: a 30-day read went
+  /// from ~60 ms to 250-600 ms between 30 and 730 days of history. Choosing
+  /// the days first, from the covering index, leaves N rows to fetch.
+  static const String _servedNewestDaysJoin =
+      'JOIN ($_servedVersions ORDER BY day_id DESC LIMIT ?) m $_servedOn';
+
   /// The result row for one day_id at the highest version this build serves
   /// (see [_servedAlgoCeiling]), with a normalized `date` alias for callers.
   /// Null if absent.
@@ -9824,8 +9834,8 @@ class LocalDb {
     // For each day_id pick MAX(algo_version), then join back for the full row.
     final rows = await db.rawQuery(
       'SELECT r.* FROM day_result r '
-      '$_servedDayJoin '
-      'ORDER BY r.day_id DESC LIMIT ?',
+      '$_servedNewestDaysJoin '
+      'ORDER BY r.day_id DESC',
       [limit],
     );
     return [for (final r in rows) _withDate(r)];
@@ -9849,8 +9859,8 @@ class LocalDb {
       'SELECT r.day_id, r.algo_version, r.computed_at, r.finalized, '
       'r.skipped, r.partial, r.rhr, r.rmssd, r.readiness '
       'FROM day_result r '
-      '$_servedDayJoin '
-      'ORDER BY r.day_id DESC LIMIT ?',
+      '$_servedNewestDaysJoin '
+      'ORDER BY r.day_id DESC',
       [limit],
     );
     return [for (final r in rows) _withDate(r)];
@@ -9896,8 +9906,8 @@ class LocalDb {
     final rows = await db.rawQuery(
       'SELECT r.day_id${cols.isEmpty ? '' : ', ${cols.join(', ')}'} '
       'FROM day_result r '
-      '$_servedDayJoin '
-      'ORDER BY r.day_id DESC LIMIT ?',
+      '$_servedNewestDaysJoin '
+      'ORDER BY r.day_id DESC',
       [limit],
     );
     return [for (final r in rows) _withDate(r)];