Top-down A/B/A controls: dispatching the 11 real compute shaders once removes
the 1.3-1.7 s first GPU Present (resource creation alone does not); 1 worker
also removes it and 8 workers bring it back. Default --gpu-far now prewarms
shaders asynchronously during shape compile (--gpu-far-no-prewarm = control).
The warm-up queue itself takes ~2.75 s, so whole view is unchanged:
CPU 1.354 s vs GPU 3.559 s (viewer clock), 1.473 vs 3.731 s (host clock).
Audits: 0 sign/topology diffs vs CPU/WARP, hashes + walk 5,642/5,642, survival.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
Re-verified f2de8fe (hashes, walk 5,642/5,642, far topology 0 diffs vs CPU and
WARP, GPU survival). The remote LOD3/4 band was a direct-GPU coverage loss
(overlapping pixels identical, surface pieces missing, e.g. (6,2,0,lod3));
LOD3/4 now mesh on CPU, root cause in the GPU route still unidentified.
A minimal first-submit repro (pools, first-touch dispatch, device flags) did
not reproduce the 2.4 s stall. Whole view: CPU 1.438 s vs GPU 4.704 s median.
Crossing probe overflowed GPU output slots: no valid crossing latency.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
Luna's session ended on an API "Bad Request" before a final report; state is
unverified by me. In the log: GPU clipped-skirt emitter (count/scan/emit,
protected signs and critical air honoured), exposed-skirt audit passing at
the end; first-present stall reproduced on every launch (2.36-2.59 s, not
exe identity/idle/CPU run) and hidden by holding the CPU-ready frame until
GPU residency. Remote LOD3-4 band still differs from CPU; draw ranges and the
one inspected LOD3 tile match, cause not yet found (one-tile probe mid-fix).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
Resumed round: checkpoint rebuilt and re-verified (parity 3,436/3,436, walk
5,642/5,642, W1/W8 hashes 44/44, far topology 0 diffs vs CPU and WARP, far
survival PASS). Remote GPU holes were missing clipped LOD skirts: tiles with
visible skirt faces now fall back to the CPU mesh path, leaving only 16 far
tiles GPU-rendered until a GPU skirt emitter exists.
My interleaved runs (SkirtSeamVerify, process start -> whole view):
CPU 1.522/1.488/1.430 s; GPU 4.271/1.749/1.659 s. A ~2.8 s first Present
stall hit only my first GPU launch; Luna saw it on every fresh launch, so the
trigger is still unidentified. Headless CPU clipmap 0.789 s.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
Luna measured the startup density-parity check at 1,049 ms, nearly all of the
~1.13 s before shape compile; it now runs after first display and still passes
3,436/3,436. CPU hashes 44/44 at 1 and 8 workers, walkability 5,642/5,642,
headless 8-worker clipmap 0.769 s. Stopped by the owner mid-round, while
auditing the remote far holes; first-launch stall and hybrid speed untouched.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
Near LOD0/1 (detail band, relief, root refinement, normals) now evaluated and
meshed on the GPU. 960 near tiles: zero sign/topology differences vs CPU and
WARP, vertex max 0.0049 mm (was 15 cm); far survival audit passes; CPU hashes
44/44 unchanged. Far connector-panel outlier (64.56 cm, LOD8) remains a
tessellation difference, and remote captures show missing far geometry on GPU.
Cold readiness (viewer clock, my interleaved runs): CPU 2.51/2.49/2.40 s,
GPU 5.05/2.68/2.80 s. The ~2.1 s Present stall hit only the first GPU launch.
Viewer spends ~1.13 s before shape compile starts (startup checks), which is
the gap between the 0.95 s benchmark and ~2.4 s on-screen.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
Whole far field on the RX 7900 XTX: 112 ms total (connector rings 61 ms). Cold hybrid 2.303 s vs
all-CPU 2.314 s (within noise): the far field is no longer on the wall-clock critical path.
0 sign/topology differences vs CPU and WARP incl. 127,401 protected and 353 thin-feature cells;
repeat GPU runs identical; far survival passes on GPU meshes; CPU hashes unchanged.
Open: CPU/GPU vertex distance mean 1.15 mm but max 64.56 cm, 247 tiles over the quantisation bound.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
Up to 32 tiles per deferred command list, one polled event per batch, no per-tile waits; CPU
upload/enqueue 723 -> 46 ms. GPU far meshes pass far survival (7,200 strata boundaries, 10,976
connectors, 0 missing/holes). But hybrid cold 4.36 s vs CPU 2.29 s: whole-tile GPU timestamps sum to
646 ms (0.58 ms/tile; step 3's 0.03 ms covered part of the work only), divergent per-thread shape
loops; CPU far-input export 1.6 worker-s. CPU 44/44 hashes unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
1,114 of 1,266 far tiles meshed on the GPU; vs CPU and vs WARP: 0 sign/topology differences,
including the protected/thin exception audit; max symmetric vertex distance 0.125 cm; repeat RX runs
identical; GPU field+mesh 0.029 ms/tile average. Strata survival 7,200/7,200, but connector survival
fails (GPU lacks the connector repair panels). Hybrid cold clipmap 5.74 s vs CPU 2.23 s: dispatch and
readback overhead, not compute (~33 ms of GPU work in total).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
Seven LOD2-8 tiles: RX 7900 XTX field+meshing 0.335 ms vs CPU generateTile 15.81 ms; repeat runs
bit-identical; CPU W1/W8 44/44 hashes unchanged. Not yet a real gain: rock/air signs still come from
CPU masks for every sample. Viewer does not draw GPU tiles yet; no whole-view timing.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ
Fr0zkaandClaude Opus 5.5