Fr0zkaandClaude Opus 5
bb8ec51939
Measurement only; no density or meshing decision changed. Full table in
PERF-ATTRIBUTION.md. The profiler self-check finally passes honestly: profiled 606.128
vs unprofiled 602.341 ms, **+0.63%** (it used to inflate 11.5x).
THE ATTRIBUTION, and it is almost embarrassingly one-sided
mesh ledger, additive, sums to the clock exactly (sum_matches_mesh = true)
shared density-grid fill 590.923 ms 97.4913%
tile parallel wall 10.972 ms 1.8102% cells, interp, normals, streams
tile merge 4.232 ms 0.6982%
pre-tile setup / prep 0.002 ms ~0%
remainder 0.0001 ms ~0%
------------------------------------------------
total 606.128 ms
GetDensityAt parent: 580.184 ms worker-wall, nested inside that 590.923 ms.
⇒ **The mesher is exonerated. Marching cubes, vertex interpolation, normals and stream
building are 2.5% combined.** The whole 4.3x is density evaluation, which is where three
of us have been looking and none of us had proven it.
WHAT IS ACTUALLY BEING DONE, per 2,248,091 samples
rooms 11,099,891 candidates -> 1,730,920 evaluated
tunnels 28,951,420 candidates -> 3,462,565 evaluated
tunnel-core 28,951,420 candidates -> 1,881,812 evaluated
~31 candidates SCANNED per sample, ~3.1 evaluated
fused detail ran on 1,079,777 and skipped 1,168,314 samples (52.0%)
software tunnel cache: 2,248,043 hits / 48 misses -- not the problem
The post-stack structural tail, which I have suspected twice, is small: StructuralTail
20.9 ms CPU / 1.9 ms wall, DensityStructuralPosts 21.9 / 2.0, PassageStructuralPosts
10.5 / 1.0 -- all nested samples against a 590.9 ms wall.
⭐⭐ AND THE FINDING THAT MATTERS MOST FOR THE GAME
clean export, classifier absent 587.991 ms
same export with the classifier 2,056.596 ms
The classifier makes generation **3.5x slower**, it is ABSENT from the export path we
have benchmarked for five days, and the GAME PATH USES IT. Its control route runs
211,289 support-column builds, 2,171,763 candidates, 1,370,314 floor queries and
2,296,243 checks -- none of which the fused export route executes at all.
⇒ Every optimisation this week was measured on a path that skips the single largest
cost the player actually pays. That is a measurement-design failure and it is mine.
Also newly visible: the full export wall is 1,004.557 ms, of which mesh is 606.128 ms
(60.3%) and OBJ WRITING is 394.273 ms (39.2%). My "0.556 s" figures have always been
mesh_seconds alone.
One real hot-path improvement landed with the instrumentation: AreCountersEnabled()
returned an unconditional `true`, so counter hooks were live in shipping builds. It is
now a relaxed load gated on diagnostic mode.
VERIFIED BY ME: build 0 errors; export 0.552 / 0.555 / 0.566 s (cf0319d was
0.563-0.566, unchanged); geometry SHA-256 b3e5f4c3..9b377 UNCHANGED.
Honest gaps, as reported: exact per-operation shares inside the density stage, physical
cache-miss counters, and a rebuilt 34f06df binary for a true A/B were all unavailable.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012aheo2crrZmHuYtPpdY2Cb