perf(dashboard): single-resolve render data cache for populated dashboard load (260610-ov3)

.planning/STATE.md

@@ -27,7 +27,7 @@ Phase: — (none active; latest shipped = Phase 1041, MERGED via PR #189 on 2026
 Plan: —
 Milestone: v3.0 FastSense Companion — SHIPPED 2026-04-30; v3.1 Plant Log Integration — SHIPPED 2026-05-19; v4.0 Multi-User LAN Concurrency — SHIPPED 2026-05 via PR #152 (parallel branch); v1.0 perf line — COMPLETE via PR #114. No milestone in flight.
 Status: Phase 1041 complete — inline time-range control (toolbar dropdown + Custom date strip) shipped; PR #189 MERGED 2026-06-03. No planned milestone in flight — repo in polish/housekeeping. Outstanding: 12 wiki-bot dup PRs were closed to 1 (#190) + workflow root-caused (260609-mcz); backlog Phase 999.1 (in-app help system) unplanned; ROADMAP v4.0 boxes stale (shipped on main via #152 — router misreports, see memory gsd-router-stale-v4-misroute).
-Last activity: 2026-06-10 - PR #197 MERGED (dashboard perf pass ~8× idle tick + crash fixes + preview restoration; quick tasks 260609-v5p, 260610-fta, 260610-g0w). Quick task 260610-hwj (review-sweep fixes batch 2: serialization round-trips, gauge MonitorTag construction crash, disk-backed export, listener leaks, marker test helper) shipped via PR #198 from claude/review-fixes-batch2.
+Last activity: 2026-06-10 - Completed quick task 260610-ov3: Optimize data loading speed in populated FastSense dashboards (DashboardEngine) — per-render Tag-data cache in FastSenseWidget (<=1 resolve per render, consume-once through the engine preview pass), O(1) ctor time-range pull, bench_dashboard_load.m. On branch claude/unruffled-gagarin-e2ca3d; MATLAB-only suite runs deferred (MCP down).
 
 ### Note on parallel v4.0 work (main branch state)
 
@@ -106,6 +106,7 @@ Other main PRs (#138, #139, #141, #144, #145, #146) auto-merged without conflict
 | 260610-g0w | Perf round 2 (profiler-driven) + latent preview bug: `getPreviewSeries` now derives bucket count from minmax output (260512 bucket-math bumps nb inside the MEX; old exact-shape check silently returned [] → slider previews missing + 0% preview-cache hits in every mex-on-path session, i.e. all test envs + any session that ran add_fastsense_private_path; clean production used the MATLAB fallback and was unaffected). Vectorized getEventMarkers extraction (isprop 8280→280 per 20 ticks); per-class ismethod cache in computeEventMarkers (~6 ms/tick); stale-banner set-skip; TimeRangeSelector isLive_ guards kill 'Invalid or deleted object' mouse-motion spam from chained WindowButtonMotionFcn closures outliving deleted selectors. Profiled idle tick 26.5→22.5 ms with previews now drawing. perf_fixes 10/10, preview_envelope 7/7 (case 6 → adaptive contract), preview_overlay 10/10, range_selector 2/2, time_window 8/8. | 2026-06-10 | e1079c20 | — | [260610-g0w-fix-getpreviewseries-mex-shape-mismatch-](./quick/260610-g0w-fix-getpreviewseries-mex-shape-mismatch-/) |
 | 260609-v5p | Speed up DashboardEngine live refresh: data-unchanged fast path in FastSenseWidget.update()/refresh() (fingerprint [n,x1,xend,yend], same append-only contract as PreviewCacheKey_) skips updateData/preview-invalidate/formatTimeAxis on idle ticks; single Tag.getXY per tick (updateTimeRangeCache(x) optional arg); refreshEventMarkers_ O(nE²)→O(nE) isequal diff; computeEventMarkers vectorized accumulators + sortrows-based dedup (max-severity-wins preserved, non-finite sev→1); getEventMarkers preallocation + per-unique-severity color lookup; vectorized formatTimeAxis_. New bench_dashboard_live.m (8 Tag-bound widgets × 50k pts + 200 events): idle tick 281→34 ms (~8×), active tick ~50→30 ms. Verified R2025b: test_dashboard_perf_fixes 9/9 (2 new), preview-envelope 7/7, events-toggle 22/22, time-window 8/8, TestDashboardEngine 18/18, TestDashboardEngineEventMarkers 8/8, TestFastSenseWidgetUpdate 2/2, TestFastSenseWidgetEventMarkers 12/12, TestDashboardDirtyFlag 6/6. Known stale test: flat test_dashboard_engine_event_markers case_render assumes one handle per marker — broken since 260508 color-group batching, fails pre- and post-change identically (Octave mirror that self-skips on Octave). | 2026-06-09 | 8cd6443f, c29be759, cbd66937, 98184f36 | — | [260609-v5p-speed-up-dashboardengine-live-refresh-pa](./quick/260609-v5p-speed-up-dashboardengine-live-refresh-pa/) |
 | 260610-hwj | Review-sweep fixes batch 2 (branch claude/review-fixes-batch2, separate PR from the perf pass): GaugeWidget.fromStruct restores Threshold (was Tag — threshold coloring dead after load) + constructor probes for allValues() (pre-v2.0-only method; MonitorTag-bound gauges crashed at construction since the migration); GroupWidget round-trips ExpandedHeight (collapsed groups were stuck collapsed after load); central themeOverride backfill in DashboardWidgetRegistry.fromStruct (dropped on load for every widget except GroupWidget); FastSense exportData routes through lineFullData (disk-backed lines exported empty columns); markerXData test helper parses batched NaN-separated marker polylines (stale since 260508). New test_review_fixes_batch2.m 4/4 R2025b / 3/3+gate Octave 11; event_markers 9/9 (first MATLAB pass ever); SerializerRoundTrip 15/15; Serializer 12/12; toolbar 19/19. | 2026-06-10 | 18387785 | — | [260610-hwj-review-sweep-fixes-batch-2-widget-serial](./quick/260610-hwj-review-sweep-fixes-batch-2-widget-serial/) |
+| 260610-ov3 | Optimize data loading speed in populated Tag-bound dashboards (LOAD path; complements 260609-v5p/260610-g0w live-tick passes): render-scoped `RenderDataCache_` in FastSenseWidget collapses 3-4 redundant Tag resolves per render() to <=1 — probe pull seeds the cache, binding (addLine for non-state kinds; State keeps addTag staircase), yInit autoscale, and updateTimeRangeCache all reuse it; consume-once lifetime (warm through DashboardEngine's post-render computePreviewEnvelope pass, cleared on preview read + refresh()/update() entry); ctor `updateTimeRangeCache()` no-arg now uses O(1) Tag.getTimeRange() instead of full getXY (also fixes disk-backed ctor range = inf/-inf). Disk widgets: 2 SQLite range queries/render → 1, and they now contribute slider-preview envelopes at load (previously silently empty). New bench_dashboard_load.m (12×50k pts, 4 disk-backed): Render 6834→6711 ms Octave (graphics-bound; data-load slice halved). Octave 11.1: render_cache 4/4, load_perf 5/5, 13 regression tests green (batch segfault = known teardown flake, isolated runs clean). DEFERRED to live MATLAB: TestDashboardEngine, TestFastSenseWidgetUpdate, TestDashboardSerializerRoundTrip suites. | 2026-06-10 | 3b7535ea | — | [260610-ov3-optimize-data-loading-speed-in-populated](./quick/260610-ov3-optimize-data-loading-speed-in-populated/) |
 
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