diag: passage vs boundary-band ceiling split (L88); coarse passage cache rejected

Verified ablations (zero passage work / zero band calls). LOD0-2 @W12: exact FI 2.27 / TN 2.25 s;
passages off FI 0.81 / TN 0.85; bands off FI 2.11 / TN 2.06. Passages cost ~1.4-1.6 s of near
readiness, bands ~0.1-0.2 s. A tile-local 4-voxel trilinear passage-delta cache increased carve
segment visits (FI 34.5M -> 56.2M) and slowed LOD0-2 (FI 2.58 -> 3.77 s); removed. No world change.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016dhxM43dnWvUu2B5Ph1iG1

Standalone/Core/include/VoxelForgeCore/VoxelForgeCore.h

@@ -138,6 +138,7 @@ namespace VoxelForgeCore
         std::uint64_t passageTileFeatureCount = 0;
         std::uint64_t passageTileRouteSegmentCandidates = 0;
         std::uint64_t passageTileMouthSegmentCandidates = 0;
+        std::uint64_t resolvedBoundaryBandQueries = 0;
         std::uint64_t passageComposerQueries = 0;
         std::uint64_t passageIterations = 0;
         std::uint64_t passageTileBoundChecks = 0;

Standalone/Core/src/ShapeWorldInternal.h

@@ -31,19 +31,37 @@
 #include <variant>
 #include <vector>
 
-// L86-only ceiling measurement. This removes passage carving/support and the transition-mouth
-// passage fade so timing can measure the best possible passage-representation gain. Never ship
-// or expose this diagnostic as a world setting.
-static bool VF_IsL86PassageCompositionDisabled()
+// L88-only composition split. These switches let the timing harness remove passage work and
+// resolved boundary-band work independently. They are diagnostic only, never world settings.
+static bool VF_IsL88DiagnosticSwitchEnabled(const char* Name)
 {
-    static const bool bDisabled = []()
-    {
-        const char* Value = std::getenv("VOXELFORGE_L86_DISABLE_PASSAGE_COMPOSITION");
-        return Value && Value[0] == '1' && Value[1] == '\0';
-    }();
+    const char* Value=std::getenv(Name);
+    return Value&&Value[0]=='1'&&Value[1]=='\0';
+}
+
+static bool VF_IsL88PassageCompositionDisabled()
+{
+    static const bool bDisabled=VF_IsL88DiagnosticSwitchEnabled(
+        "VOXELFORGE_L88_DISABLE_PASSAGES")
+        ||VF_IsL88DiagnosticSwitchEnabled("VOXELFORGE_L86_DISABLE_PASSAGE_COMPOSITION");
     return bDisabled;
 }
 
+static bool VF_IsL88BoundaryBandsDisabled()
+{
+    static const bool bDisabled=VF_IsL88DiagnosticSwitchEnabled(
+        "VOXELFORGE_L88_DISABLE_BOUNDARY_BANDS")
+        ||VF_IsL88DiagnosticSwitchEnabled("VOXELFORGE_L86_DISABLE_PASSAGE_COMPOSITION");
+    return bDisabled;
+}
+
+static bool VF_IsL88AllowPassageAblationWalkabilityFailure()
+{
+    static const bool bEnabled=VF_IsL88DiagnosticSwitchEnabled(
+        "VOXELFORGE_L88_ALLOW_PASSAGE_ABLATION_WALKABILITY_FAILURE");
+    return bEnabled;
+}
+
 // Standalone-only world compiler. It compiles the runtime room/tunnel/passages into
 // axis-line intervals, composes rock/cave signs into packed Z-column words, then displaces
 // only the conservative surface band. The copied Unreal generator remains the A/B reference.
@@ -197,7 +215,6 @@ public:
             std::ptrdiff_t first=-1,end=-1;
             std::vector<std::uint8_t> activeNodes;
         };
-
         FScopedPassageTileQueries(const FStandaloneShapeWorld& shape,
             const std::array<std::int64_t,3>& minimumSubvoxels,
             const std::array<std::int64_t,3>& maximumSubvoxels,
@@ -208,7 +225,9 @@ public:
         {
             mayContainResolvedBoundaryBand_=shape.ResolvedBoundaryBandsIntersectSubvoxelRange(
                 minimumSubvoxels_[2],maximumSubvoxels_[2]);
-            const bool disablePassageComposition = VF_IsL86PassageCompositionDisabled();
+            const bool disablePassageComposition=VF_IsL88PassageCompositionDisabled();
+            const bool disableBoundaryBands=VF_IsL88BoundaryBandsDisabled();
+            if(disableBoundaryBands)mayContainResolvedBoundaryBand_=false;
             mayContainTransitionPassageFade_ = !disablePassageComposition
                 && shape.ResolvedTransitionPassageFadeIntersectsTileXY(
                     minimumSubvoxels_, maximumSubvoxels_);
@@ -930,6 +949,9 @@ public:
 #endif
         (void)X;(void)Y;
         const auto* tileQueries=ActivePassageTileQueries;
+        if(tileQueries&&tileQueries->matches(*this))
+            if(auto* profile=tileQueries->profileStats())
+                ++profile->resolvedBoundaryBandQueries;
         if(tileQueries&&tileQueries->matches(*this))
         {
             if(!tileQueries->mayContainResolvedBoundaryBand())
@@ -2256,9 +2278,11 @@ public:
         // mouth that crosses a wide transition band. Keep that opt-in field whole;
         // its host-rock value already supplies the ceiling and bedrock.
         const bool disablePassageComposition=!nativeLattice
-            &&VF_IsL86PassageCompositionDisabled();
+            &&VF_IsL88PassageCompositionDisabled();
+        const bool disableBoundaryBands=!nativeLattice
+            &&VF_IsL88BoundaryBandsDisabled();
         float boundary=graphDensity;
-        if(!nativeLattice&&!disablePassageComposition)
+        if(!nativeLattice&&!disableBoundaryBands)
         {
             VoxelForgeCore::Linux77Profiler::FScopedPhase l77BandsPhase(
                 VoxelForgeCore::Linux77Profiler::EPhase::Bands);
@@ -3019,11 +3043,22 @@ public:
         // Route validation is world-wide. Detail regions reuse the same authored route data and
         // do not need to repeat the 5,642-point world audit for every entering tile group.
         Substage=Clock::now();
-        if(bValidatePassageRoutes&&!ValidatePassageRoutes())
+        const bool bPassageRoutesValid=!bValidatePassageRoutes||ValidatePassageRoutes();
+        if(!bPassageRoutesValid)
+        {
+            if(VF_IsL88PassageCompositionDisabled()
+                &&!VF_IsL88BoundaryBandsDisabled()
+                &&VF_IsL88AllowPassageAblationWalkabilityFailure())
+            {
+                std::printf("[L88PassageAblation] route walkability failed as expected; "
+                    "continuing only to measure passage-off/bands-on readiness\n");
+            }
+            else
             {
                 Error="compiled shape world contains a solid passage centreline sample";
                 return false;
             }
+        }
         Stats.PassageValidationSeconds=std::chrono::duration<double>(Clock::now()-Substage).count();
         Built=true;
         if(bIncludeFarWorld)BuildFarWorld();

Standalone/Research/WorldAssemblerM3/Linux88/REPORT.md

@@ -0,0 +1,35 @@
+# Linux 88 — passage and boundary cost
+
+## Ceiling split
+
+L80 protocol: one warmup, then three interleaved measured runs per mode, worker count and stratum. Values are median seconds to LOD0–2 ready / whole view ready.
+
+| Stratum | Workers | Exact | Passages off, bands on | Bands off, passages on |
+|---|---:|---:|---:|---:|
+| FI | 8 | 2.419 / 3.696 | 0.808 / 1.738 | 2.306 / 3.556 |
+| FI | 12 | 2.273 / 3.463 | 0.812 / 1.683 | 2.114 / 3.290 |
+| TN | 8 | 2.458 / 3.624 | 0.912 / 1.814 | 2.222 / 3.308 |
+| TN | 12 | 2.253 / 3.294 | 0.851 / 1.683 | 2.056 / 3.061 |
+
+Passage composition costs about 1.40–1.61 s of FI/TN LOD0–2 readiness. Boundary bands cost about 0.11–0.24 s. The split counters confirmed the ablations: passages-off had zero passage queries, iterations, carve/support visits and relief calls, while retaining 11.39M FI / 7.72M TN band calls in profiled tiles. Bands-off had zero band calls while passage iterations remained 14.06M FI / 12.43M TN. The profile covered 629 FI and 614 TN near tiles. Passage-off intentionally failed the route walkability check because the remaining bands close an authored mouth; a split-only diagnostic continued the timing run.
+
+Exact-field readiness across all four strates:
+
+| Stratum | W8 LOD0–2 / whole | W12 LOD0–2 / whole |
+|---|---:|---:|
+| SurfaceWorld | 1.093 / 2.340 | 1.024 / 2.157 |
+| FloatingIslands | 2.419 / 3.696 | 2.273 / 3.463 |
+| TunnelNetwork | 2.458 / 3.624 | 2.253 / 3.294 |
+| VerticalShafts | 1.312 / 2.386 | 1.128 / 2.080 |
+
+## Prototype and decision
+
+I tested a tile-local 4-voxel trilinear cache of passage-composition deltas, with exact evaluation near or across the zero surface. It did not remove enough route work: instrumented FI/TN runs recorded 4.75M / 7.71M exact coarse-node evaluations, and carve-segment visits increased from 34.5M / 33.1M to 56.2M / 76.5M.
+
+Two unprofiled interleaved W8 pairs confirmed the regression. FI LOD0–2 median rose from 2.583 s exact to 3.765 s coarse; TN rose from 2.646 s to 4.649 s. Whole-view medians rose from 3.957 to 8.708 s for FI and 3.735 to 7.976 s for TN. The prototype was removed from source.
+
+The pre-measurement acceptance bar was max displacement ≤5 cm, mean ≤1 cm per stratum, and zero sign flips on canonical walk-floor samples. Displacement was not measured. The prototype stopped at the speed gate, so post-prototype passage audits, captures, and Clang/GCC W1/W8/W12 comparisons were not run. No evaluator version bump or hash re-pins were made; version remains 214. The fast tier passed on the cleaned exact-field source: 274 checks in 311.3 s, stamp `81a934b80ed90d2ab0137345d15688a9bd201e4ec6ce7af94b08f4cb4e77c1a3`.
+
+## Runs
+
+All benchmark and verification jobs used CPUs 0–11; headless jobs were capped at 6 GiB. No run exceeded 30 minutes. The timing and per-tile work logs are under `Saved/Linux/l88/ceiling-split/` and `Saved/Linux/l88/coarse-prototype/`; the fast-tier log and summary are under `Saved/Linux/l88/logs/fast-tier.log` and `Saved/Linux/l88/verify-fast/fast-summary.json`. No Unreal `Source/` files changed, so no UE build was needed. No commit, push, or stash was made.

Standalone/Research/WorldAssemblerM3/Linux88/RunL88CeilingSplit.py

@@ -0,0 +1,198 @@
+#!/usr/bin/env python3
+"""Measure passage and boundary-band ceilings independently under the L80 protocol."""
+from __future__ import annotations
+
+import argparse
+import json
+import re
+import statistics
+import subprocess
+import time
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[4]
+OUT = ROOT / "Saved/Linux/l88/ceiling-split"
+DATA = ROOT / "Standalone/data/owner_world.json"
+BINARY = ROOT / "Saved/Linux/l88/bin/VoxelForgeCoreHeadless-l88-clang19"
+STRATA = {
+    "S0": {"id": 0, "camera": (8.0, 16.0, -372.2626953125), "near": 1408, "whole": 2850},
+    "FI": {"id": 1, "camera": (25.8369140625, 3.19921875, -737.0), "near": 1216, "whole": 2249},
+    "TN": {"id": 2, "camera": (19.166015625, -14.2001953125, -753.3740234375), "near": 1344, "whole": 2233},
+    "S3": {"id": 3, "camera": (-20.0625, -5.068359375, -900.353515625), "near": 1344, "whole": 2329},
+}
+WORKERS = (8, 12)
+MODES = ("direct", "passages_off", "bands_off")
+PIPELINE = re.compile(r"^\[StreamPipeline\] (.*)$", re.M)
+FIELDS = re.compile(r"([a-zA-Z0-9_]+)=([^ ]+)")
+NEAR = re.compile(
+    r"^\[WorldAssemblerNearLODReady\] lods=0-2 tiles=(\d+)/(\d+) cold_ready_s=([0-9.]+)$", re.M)
+PASSAGE_TILE = re.compile(r"^\[PassageComposerTile\] (.*)$", re.M)
+STAMP = re.compile(r"^\[VoxelForgeSourceStamp\] sha256=(\S+)$", re.M)
+
+
+def base_command(stratum: str, workers: int, mode: str, profile: bool = False) -> list[str]:
+    spec = STRATA[stratum]
+    camera = ",".join(f"{value:.12f}" for value in spec["camera"]) + ",0,0"
+    child = [
+        str(BINARY), str(DATA), "--world-assembler-prototype", "--stream-benchmark",
+        "--stream-pipeline", f"--workers={workers}", "--clip-radius=3",
+        "--max-clip-level=8", "--max-level=8", f"--camera={camera}",
+        "--profile-lod-work", "--stream-scheduler-policy=3",
+    ]
+    if profile:
+        child.append("--profile-passage-composer")
+    env = ["VOXELFORGE_L81_PASSAGE_BOUND_PADDING_VOXELS=0"]
+    if mode == "passages_off":
+        env.extend(("VOXELFORGE_L88_DISABLE_PASSAGES=1",
+                    "VOXELFORGE_L88_ALLOW_PASSAGE_ABLATION_WALKABILITY_FAILURE=1"))
+    elif mode == "bands_off":
+        env.append("VOXELFORGE_L88_DISABLE_BOUNDARY_BANDS=1")
+    return [
+        "taskset", "-c", "0-11", "prlimit", "--as=6442450944", "--", "env",
+        *env, "timeout", "1740s", *child,
+    ]
+
+
+def execute(stratum: str, workers: int, mode: str, phase: str,
+            replicate: int = 0, profile: bool = False) -> dict:
+    OUT.mkdir(parents=True, exist_ok=True)
+    label = f"{stratum.lower()}-w{workers}-{mode}-{phase}"
+    if replicate:
+        label += f"-r{replicate}"
+    if profile:
+        label += "-profile"
+    log = OUT / f"{label}.log"
+    started = time.monotonic()
+    with log.open("w", encoding="utf-8") as stream:
+        result = subprocess.run(base_command(stratum, workers, mode, profile), cwd=ROOT,
+                                stdout=stream, stderr=subprocess.STDOUT,
+                                check=False, timeout=1750)
+    output = log.read_text(encoding="utf-8", errors="replace")
+    pipeline, near, stamp = PIPELINE.search(output), NEAR.search(output), STAMP.search(output)
+    if result.returncode or pipeline is None or near is None or stamp is None:
+        raise RuntimeError(f"run failed or required output is missing: {log}; exit={result.returncode}")
+    spec = STRATA[stratum]
+    near_counts = (int(near.group(1)), int(near.group(2)))
+    if near_counts != (spec["near"], spec["near"]):
+        raise RuntimeError(f"incomplete near set in {log}: {near_counts}")
+    fields = dict(FIELDS.findall(pipeline.group(1)))
+    whole_counts = tuple(int(value) for value in fields["whole_tiles"].split("/"))
+    if whole_counts != (spec["whole"], spec["whole"]):
+        raise RuntimeError(f"incomplete whole view in {log}: {whole_counts}")
+    ablation_walkability = "[L88PassageAblation]" in output
+    if (mode == "passages_off") != ablation_walkability:
+        raise RuntimeError(f"passage ablation walkability marker unexpected in {log}")
+    row = {
+        "stratum": stratum, "workers": workers, "mode": mode, "phase": phase,
+        "replicate": replicate, "profile": profile, "exit_code": result.returncode,
+        "wall_s": round(time.monotonic() - started, 3), "source_stamp": stamp.group(1),
+        "lod02_ready_s": float(near.group(3)),
+        "whole_view_ready_s": float(fields["whole_view_ready"].removesuffix("s")),
+        "shape_s": float(fields["shape"].removesuffix("s")),
+        "far_shape_s": float(fields["far_shape"].removesuffix("s")),
+        "ablation_walkability_failed": ablation_walkability,
+        "near_tiles": spec["near"], "whole_tiles": spec["whole"],
+        "log": str(log.relative_to(ROOT)),
+    }
+    if profile:
+        total = {name: 0 for name in (
+            "boundary_band_queries", "queries", "passage_iterations",
+            "carve_segment_visits", "support_segment_visits", "relief_field_calls",
+        )}
+        profiled_tiles = 0
+        for match in PASSAGE_TILE.finditer(output):
+            fields = dict(FIELDS.findall(match.group(1)))
+            if int(fields["key"].rsplit("lod", 1)[1].rstrip(")")) > 2:
+                continue
+            profiled_tiles += 1
+            for name in total:
+                total[name] += int(fields[name])
+        if not profiled_tiles:
+            raise RuntimeError(f"passage/band profile rows missing in {log}")
+        row.update({f"profile_{name}": value for name, value in total.items()})
+        row["profiled_near_tiles"] = profiled_tiles
+    print("[L88CeilingSplitRun] " + json.dumps(row, sort_keys=True), flush=True)
+    return row
+
+
+def profile_modes() -> list[dict]:
+    rows = [execute(stratum, 8, mode, "profile", profile=True)
+            for stratum in ("FI", "TN") for mode in MODES]
+    for stratum in ("FI", "TN"):
+        subset = {row["mode"]: row for row in rows if row["stratum"] == stratum}
+        direct, passages, bands = (subset[name] for name in MODES)
+        if direct["profile_boundary_band_queries"] == 0 or direct["profile_queries"] == 0:
+            raise RuntimeError(f"direct profile did not exercise both paths for {stratum}")
+        if passages["profile_boundary_band_queries"] == 0 or any(
+            passages[f"profile_{name}"] != 0
+            for name in ("queries", "passage_iterations", "carve_segment_visits",
+                         "support_segment_visits", "relief_field_calls")
+        ):
+            raise RuntimeError(f"passages-off profile did not isolate the band path for {stratum}")
+        if bands["profile_boundary_band_queries"] != 0 or any(
+            bands[f"profile_{name}"] == 0
+            for name in ("queries", "passage_iterations", "carve_segment_visits")
+        ):
+            raise RuntimeError(f"bands-off profile did not preserve passage work for {stratum}")
+    (OUT / "profile-summary.json").write_text(json.dumps(rows, indent=2) + "\n", encoding="utf-8")
+    return rows
+
+
+def timing_matrix() -> list[dict]:
+    # One warmup for each complete stratum/worker/mode window.
+    for stratum in STRATA:
+        for workers in WORKERS:
+            for mode in MODES:
+                execute(stratum, workers, mode, "warmup")
+    orders = (
+        ((8, "direct"), (8, "passages_off"), (8, "bands_off"),
+         (12, "bands_off"), (12, "passages_off"), (12, "direct")),
+        ((12, "passages_off"), (12, "direct"), (12, "bands_off"),
+         (8, "bands_off"), (8, "direct"), (8, "passages_off")),
+        ((8, "bands_off"), (8, "direct"), (8, "passages_off"),
+         (12, "direct"), (12, "passages_off"), (12, "bands_off")),
+    )
+    measured = []
+    for stratum in STRATA:
+        for replicate, order in enumerate(orders, 1):
+            for workers, mode in order:
+                measured.append(execute(stratum, workers, mode, "measured", replicate))
+                (OUT / "runs-partial.json").write_text(
+                    json.dumps(measured, indent=2) + "\n", encoding="utf-8")
+    summary = []
+    for stratum in STRATA:
+        for workers in WORKERS:
+            for mode in MODES:
+                subset = [r for r in measured if r["stratum"] == stratum
+                          and r["workers"] == workers and r["mode"] == mode]
+                if len(subset) != 3:
+                    raise RuntimeError(f"expected 3 measured runs for {stratum} W{workers} {mode}")
+                item = {"stratum": stratum, "workers": workers, "mode": mode,
+                        "measured_runs": len(subset)}
+                for metric in ("lod02_ready_s", "whole_view_ready_s", "shape_s", "far_shape_s"):
+                    values = [r[metric] for r in subset]
+                    item[metric] = values
+                    item[f"{metric}_median"] = statistics.median(values)
+                summary.append(item)
+    (OUT / "summary.json").write_text(
+        json.dumps({"runs": measured, "summary": summary}, indent=2) + "\n",
+        encoding="utf-8")
+    return measured
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--profiles-only", action="store_true")
+    parser.add_argument("--timing-only", action="store_true")
+    args = parser.parse_args()
+    if not BINARY.is_file() or not DATA.is_file():
+        raise SystemExit(f"missing input: {BINARY} or {DATA}")
+    if not args.timing_only:
+        profile_modes()
+    if not args.profiles_only:
+        timing_matrix()
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

Standalone/Source/StreamingWorld.h

@@ -1493,13 +1493,14 @@ private:
             static_cast<unsigned long long>(D.islandSharedCacheConflictReplacements),
             static_cast<double>(D.islandSharedCacheLockWaitNanoseconds)/1000.0);
         if(D.passageComposerProfiled)
-            std::printf("[PassageComposerTile] key=(%d,%d,%d,lod%d) worker_ms=%.3f samples=%llu native_field_calls=%llu features=%llu route_candidates=%llu mouth_candidates=%llu queries=%llu passage_iterations=%llu tile_bound_checks=%llu tile_bound_rejects=%llu tile_bound_skipped_iterations=%llu upper_mouth_checks=%llu column_candidates=%llu column_distance_calls=%llu negative_bounds=%llu negative_rejects=%llu positive_bounds=%llu positive_rejects=%llu carve_segment_visits=%llu smooth_carve_joins=%llu support_segment_visits=%llu smooth_support_joins=%llu support_capsule_checks=%llu later_bore_checks=%llu other_capsule_checks=%llu mouth_support_calls=%llu mouth_route_segment_checks=%llu relief_field_calls=%llu smoothstep_evaluations=%llu\n",
+            std::printf("[PassageComposerTile] key=(%d,%d,%d,lod%d) worker_ms=%.3f samples=%llu native_field_calls=%llu features=%llu route_candidates=%llu mouth_candidates=%llu boundary_band_queries=%llu queries=%llu passage_iterations=%llu tile_bound_checks=%llu tile_bound_rejects=%llu tile_bound_skipped_iterations=%llu upper_mouth_checks=%llu column_candidates=%llu column_distance_calls=%llu negative_bounds=%llu negative_rejects=%llu positive_bounds=%llu positive_rejects=%llu carve_segment_visits=%llu smooth_carve_joins=%llu support_segment_visits=%llu smooth_support_joins=%llu support_capsule_checks=%llu later_bore_checks=%llu other_capsule_checks=%llu mouth_support_calls=%llu mouth_route_segment_checks=%llu relief_field_calls=%llu smoothstep_evaluations=%llu\n",
                 Event.Key.Coord.X,Event.Key.Coord.Y,Event.Key.Coord.Z,Event.Key.Level,
                 Event.WorkerMilliseconds,static_cast<unsigned long long>(Event.DensitySamples),
                 static_cast<unsigned long long>(D.fieldCalls),
                 static_cast<unsigned long long>(D.passageTileFeatureCount),
                 static_cast<unsigned long long>(D.passageTileRouteSegmentCandidates),
                 static_cast<unsigned long long>(D.passageTileMouthSegmentCandidates),
+                static_cast<unsigned long long>(D.resolvedBoundaryBandQueries),
                 static_cast<unsigned long long>(D.passageComposerQueries),
                 static_cast<unsigned long long>(D.passageIterations),
                 static_cast<unsigned long long>(D.passageTileBoundChecks),