复用选股日快照视图

crates/fidc-core/src/data.rs

@@ -1335,6 +1335,55 @@ pub struct DataSet {
     futures_params_by_symbol: Arc<HashMap<String, Vec<FuturesTradingParameter>>>,
 }
 
+struct DailySymbolRows<'a, T> {
+    rows: &'a [T],
+    symbol_ids: &'a [u32],
+    row_positions: Option<&'a [u32]>,
+}
+
+impl<'a, T> DailySymbolRows<'a, T> {
+    fn get(&self, symbol_id: u32) -> Option<&'a T> {
+        if let Some(positions) = self.row_positions {
+            let position = positions.get(symbol_id as usize).copied()?;
+            if position == MISSING_ROW_POSITION {
+                return None;
+            }
+            return self.rows.get(position as usize);
+        }
+        find_by_symbol_id(self.rows, self.symbol_ids, symbol_id)
+    }
+}
+
+/// Borrowed, immutable snapshots for one trading date.
+///
+/// A strategy evaluates thousands of symbols for the same date. Resolving the
+/// date in three BTreeMaps for every symbol is unnecessary; this view freezes
+/// the already indexed slices once and keeps all lookups read-only.
+pub(crate) struct DailySnapshotView<'a> {
+    market: DailySymbolRows<'a, DailyMarketSnapshot>,
+    factor_rows: &'a [DailyFactorSnapshot],
+    factor_symbol_ids: &'a [u32],
+    candidates: DailySymbolRows<'a, CandidateEligibility>,
+}
+
+impl<'a> DailySnapshotView<'a> {
+    pub(crate) fn market(&self, symbol_id: u32) -> Option<&'a DailyMarketSnapshot> {
+        self.market.get(symbol_id)
+    }
+
+    pub(crate) fn candidate(&self, symbol_id: u32) -> Option<&'a CandidateEligibility> {
+        self.candidates.get(symbol_id)
+    }
+
+    pub(crate) fn factor_rows(&self) -> &'a [DailyFactorSnapshot] {
+        self.factor_rows
+    }
+
+    pub(crate) fn factor_symbol_ids(&self) -> &'a [u32] {
+        self.factor_symbol_ids
+    }
+}
+
 #[derive(Debug, Clone, Copy)]
 pub(crate) struct StandardRollingMeans {
     pub close: [Option<f64>; 7],
@@ -1868,6 +1917,52 @@ impl DataSet {
         )
     }
 
+    pub(crate) fn daily_snapshot_view(&self, date: NaiveDate) -> DailySnapshotView<'_> {
+        fn rows_on<'a, T>(
+            date: NaiveDate,
+            rows_by_date: &'a BTreeMap<NaiveDate, Vec<T>>,
+            symbol_ids_by_date: &'a BTreeMap<NaiveDate, Vec<u32>>,
+            row_positions_by_date: &'a Option<DenseRowPositionIndex>,
+        ) -> DailySymbolRows<'a, T> {
+            DailySymbolRows {
+                rows: rows_by_date.get(&date).map(Vec::as_slice).unwrap_or(&[]),
+                symbol_ids: symbol_ids_by_date
+                    .get(&date)
+                    .map(Vec::as_slice)
+                    .unwrap_or(&[]),
+                row_positions: row_positions_by_date
+                    .as_ref()
+                    .and_then(|positions| positions.get(&date))
+                    .map(Vec::as_slice),
+            }
+        }
+
+        DailySnapshotView {
+            market: rows_on(
+                date,
+                &self.market_by_date,
+                &self.market_symbol_ids_by_date,
+                &self.market_row_positions_by_date,
+            ),
+            factor_rows: self
+                .factor_by_date
+                .get(&date)
+                .map(Vec::as_slice)
+                .unwrap_or(&[]),
+            factor_symbol_ids: self
+                .factor_symbol_ids_by_date
+                .get(&date)
+                .map(Vec::as_slice)
+                .unwrap_or(&[]),
+            candidates: rows_on(
+                date,
+                &self.candidate_by_date,
+                &self.candidate_symbol_ids_by_date,
+                &self.candidate_row_positions_by_date,
+            ),
+        }
+    }
+
     fn market_series(&self, symbol: &str) -> Option<&SymbolPriceSeries> {
         self.market_series_by_symbol.get(symbol).map(Arc::as_ref)
     }
@@ -4775,11 +4870,16 @@ mod tests {
 
         for symbol in ["000001.SZ", "600000.SH"] {
             let symbol_id = data.symbol_id(symbol).unwrap();
+            let day = data.daily_snapshot_view(date);
             assert_eq!(
                 data.market_by_symbol_id(date, symbol_id)
                     .map(|row| row.symbol.as_str()),
                 Some(symbol)
             );
+            assert_eq!(
+                day.market(symbol_id).map(|row| row.symbol.as_str()),
+                Some(symbol)
+            );
             assert_eq!(
                 data.factor_by_symbol_id(date, symbol_id)
                     .map(|row| row.symbol.as_str()),
@@ -4790,15 +4890,138 @@ mod tests {
                     .map(|row| row.symbol.as_str()),
                 Some(symbol)
             );
+            assert_eq!(
+                day.candidate(symbol_id).map(|row| row.symbol.as_str()),
+                Some(symbol)
+            );
         }
 
         let signal_id = data.symbol_id("000300.SH").unwrap();
+        let day = data.daily_snapshot_view(date);
         assert_eq!(
             data.market_by_symbol_id(date, signal_id).map(|row| row.symbol.as_str()),
             Some("000300.SH")
         );
         assert!(data.factor_by_symbol_id(date, signal_id).is_none());
         assert!(data.candidate_by_symbol_id(date, signal_id).is_none());
+        assert!(day.candidate(signal_id).is_none());
+    }
+
+    #[test]
+    #[ignore = "manual component benchmark"]
+    fn benchmark_daily_snapshot_view_lookup() {
+        use std::hint::black_box;
+        use std::time::Instant;
+
+        let date = NaiveDate::parse_from_str("2025-01-02", "%Y-%m-%d").unwrap();
+        let symbol_count = 6_000usize;
+        let symbols = (0..symbol_count)
+            .map(|index| format!("{index:06}.SZ"))
+            .collect::<Vec<_>>();
+        let instruments = symbols
+            .iter()
+            .map(|symbol| Instrument {
+                symbol: symbol.clone(),
+                name: symbol.clone(),
+                board: "SZ".to_string(),
+                round_lot: 100,
+                listed_at: None,
+                delisted_at: None,
+                status: "active".to_string(),
+            })
+            .collect::<Vec<_>>();
+        let market = symbols
+            .iter()
+            .enumerate()
+            .map(|(index, symbol)| {
+                let mut row = market_row(
+                    "2025-01-02",
+                    10.0 + index as f64 / 1000.0,
+                    1_000_000,
+                );
+                row.symbol = symbol.clone();
+                row
+            })
+            .collect::<Vec<_>>();
+        let factors = symbols
+            .iter()
+            .enumerate()
+            .map(|(index, symbol)| DailyFactorSnapshot {
+                date,
+                symbol: symbol.clone(),
+                market_cap_bn: 10.0 + index as f64 / 1000.0,
+                free_float_cap_bn: 8.0,
+                pe_ttm: 10.0,
+                turnover_ratio: None,
+                effective_turnover_ratio: None,
+                extra_factors: NumericFactorMap::new(),
+            })
+            .collect::<Vec<_>>();
+        let candidates = symbols
+            .iter()
+            .map(|symbol| CandidateEligibility {
+                date,
+                symbol: symbol.clone(),
+                is_st: false,
+                is_star_st: false,
+                is_new_listing: false,
+                is_paused: false,
+                allow_buy: true,
+                allow_sell: true,
+                is_kcb: false,
+                is_one_yuan: false,
+                risk_level_code: None,
+            })
+            .collect::<Vec<_>>();
+        let data = DataSet::from_components(
+            instruments,
+            market,
+            factors,
+            candidates,
+            vec![benchmark_row("2025-01-02", 20.0)],
+        )
+        .unwrap();
+        let symbol_ids = symbols
+            .iter()
+            .map(|symbol| data.symbol_id(symbol).unwrap())
+            .collect::<Vec<_>>();
+        let rounds = 200usize;
+
+        let started = Instant::now();
+        let mut baseline_sum = 0.0;
+        for _ in 0..rounds {
+            for symbol_id in symbol_ids.iter().copied() {
+                baseline_sum += black_box(
+                    data.market_by_symbol_id(date, symbol_id).unwrap().close
+                        + data
+                            .candidate_by_symbol_id(date, symbol_id)
+                            .unwrap()
+                            .allow_buy as u8 as f64,
+                );
+            }
+        }
+        let baseline = started.elapsed();
+
+        let day = data.daily_snapshot_view(date);
+        let started = Instant::now();
+        let mut view_sum = 0.0;
+        for _ in 0..rounds {
+            for symbol_id in symbol_ids.iter().copied() {
+                view_sum += black_box(
+                    day.market(symbol_id).unwrap().close
+                        + day.candidate(symbol_id).unwrap().allow_buy as u8 as f64,
+                );
+            }
+        }
+        let view = started.elapsed();
+        assert_eq!(baseline_sum, view_sum);
+        println!(
+            "daily_snapshot_view rows={} rounds={} baseline_seconds={:.6} view_seconds={:.6}",
+            symbol_count,
+            rounds,
+            baseline.as_secs_f64(),
+            view.as_secs_f64(),
+        );
     }
 
     #[test]

crates/fidc-core/src/platform_expr_strategy.rs

@@ -8886,8 +8886,10 @@ impl PlatformExprStrategy {
     ) -> (Vec<EligibleUniverseSnapshot>, Vec<FidcRiskDecisionAudit>) {
         let mut rows = Vec::new();
         let mut decisions = Vec::new();
-        let factor_rows = ctx.data.factor_snapshot_rows_on(factor_date);
-        let factor_symbol_ids = ctx.data.factor_symbol_ids_on(factor_date);
+        let execution_day = ctx.data.daily_snapshot_view(date);
+        let factor_day = ctx.data.daily_snapshot_view(factor_date);
+        let factor_rows = factor_day.factor_rows();
+        let factor_symbol_ids = factor_day.factor_symbol_ids();
         debug_assert_eq!(factor_rows.len(), factor_symbol_ids.len());
         for (factor, symbol_id) in factor_rows.iter().zip(factor_symbol_ids.iter().copied()) {
             if ctx.has_dynamic_universe() && !ctx.dynamic_universe_contains(&factor.symbol) {
@@ -8895,14 +8897,14 @@ impl PlatformExprStrategy {
             }
             let synthetic_candidate;
             let candidate =
-                if let Some(candidate) = ctx.data.candidate_by_symbol_id(date, symbol_id) {
+                if let Some(candidate) = execution_day.candidate(symbol_id) {
                     candidate
                 } else {
                     synthetic_candidate =
                         crate::data::missing_candidate_risk_state(date, &factor.symbol);
                     &synthetic_candidate
                 };
-            let Some(market) = ctx.data.market_by_symbol_id(date, symbol_id) else {
+            let Some(market) = execution_day.market(symbol_id) else {
                 continue;
             };
             let (reject_from_universe, selection_decision) = if collect_risk_decisions {

docs/market-day-view-benchmark-20260831.md

@@ -0,0 +1,51 @@
+# Market Day View Component Benchmark
+
+Date: 2026-08-31
+
+## Scope
+
+The platform-expression selection loop already iterates one factor slice for a
+single trading date. The previous implementation still resolved the same date
+in the market and candidate `BTreeMap` for every symbol. `DailySnapshotView`
+borrows the existing immutable market/factor/candidate slices and dense row
+position arrays once per date, then performs only `symbol_id -> row` lookups.
+
+The view does not copy snapshots, cache strategy results, share account state,
+or change missing-row behavior. The optimization is independent of strategy
+text, thresholds, rolling windows, execution mode and portfolio size.
+
+## Release Component A/B
+
+Contract:
+
+- 6,000 symbols;
+- 200 complete lookup rounds;
+- each lookup reads market close and candidate `allow_buy`;
+- baseline and view checksums must be exactly equal;
+- `cargo test --release`, system allocator, local macOS host.
+
+| Round | Baseline seconds | Day view seconds |
+| ---: | ---: | ---: |
+| 1 | 0.009000 | 0.002939 |
+| 2 | 0.004370 | 0.001555 |
+| 3 | 0.004274 | 0.001578 |
+
+Median component time changed from `0.004370s` to `0.001578s`, an observed
+reduction of about `63.9%` (`2.77x`). This is a component result only and is
+not a complete backtest SLA.
+
+## Correctness Gates
+
+- sparse market-only symbols remain absent from factor/candidate views;
+- dense and binary-search fallback lookup semantics remain unchanged;
+- full engine suite: 529 passed, 3 ignored manual benchmarks;
+- next-open execution-day risk, minute matching, fees, slippage, volume limits,
+  corporate actions, delisting and futures tests all passed.
+
+## Deployment Status
+
+Not deployed. The 177 FIDC-managed Boris factor task is still active, so no
+Source Lake, backtest service or engine restart is allowed. After the task
+ends naturally, acceptance must use the same frozen bundle and compare daily
+selection, orders, fills, holdings, NAV, risk facts and canonical digest for
+multiple daily/minute and fixed/dynamic-universe strategies.