acdream/docs/research/2026-07-24-slice-c-prepared-asset-cutover-report.md

Slice C prepared-asset cutover report

Date: 2026-07-24

Measured binary: b1ad4b7c0a0a519ab36d707baba74890634e6028

Result: pass

Slice C moves production world-mesh preparation out of the live client. acdream-bake converts installed retail DAT geometry and material metadata into an immutable acdream.pak; production streaming now reads those prepared records without reconstructing the same DAT object graphs during portals. DAT remains authoritative for simulation, UI, animation, dynamic appearance, physics, audio, and effects.

The user's connected screenshot review passed on 2026-07-24. Raw screenshot differences against Slice A were caused by non-identical world lighting and post-turn camera state; the user confirmed the prepared path's geometry, materials, textures, and world presentation look correct. No tolerance was widened and no world pixels were masked to obtain that result.

Production package

Measure	Result
Format / bake-tool version	1 / 3
GfxObj keys	15,318
Setup keys	5,935
EnvCell keys	729,888
Total TOC keys	751,141
Portal / Cell / HighRes / Language iteration	2072 / 982 / 497 / 994
Artifact size	29,562,150,456 bytes (27.53 GiB)
Header, TOC, ranges, aliases, CRCs, and iterations	pass

Bake-tool version 3 persists each texture batch's exact translucency classification. That lets the render thread consume the prepared record directly instead of rebuilding a GfxObjMesh solely to recover material metadata. The validated package is a required machine-local production input beside the DAT files; it is not a repository artifact.

Focused installed-DAT validation passed 20 prepared-source, serializer, and pak-equivalence tests plus two full-bake determinism/artifact tests. The complete Release suite passed 8,076 tests with five skips and zero failures.

Connected physical-display result

All three runs used the committed reference AMD display configuration, a source-matched Release binary, the same deterministic routes as Slice A, and normal retained gameplay UI. Every destination materialized, movement/jump/ combat exercises passed, and every client disconnected gracefully.

Capture	CPU p50 / p95 / p99	GPU p50 / p95 / p99	Frame allocation max
Capped Slice A	4.287 / 6.972 / 9.404 ms	1.702 / 3.261 / 3.847 ms	203.5 MiB
Capped Slice C	4.247 / 5.873 / 7.814 ms	1.836 / 2.694 / 3.078 ms	46.8 MiB
Uncapped Slice A	1.520 / 5.694 / 7.825 ms	0.897 / 3.239 / 3.406 ms	202.9 MiB
Uncapped Slice C	1.409 / 4.909 / 6.496 ms	0.832 / 2.510 / 2.706 ms	39.9 MiB
Dense Arwic Slice A	3.672 / 6.561 / 14.121 ms	2.476 / 3.284 / 3.752 ms	28.5 MiB
Dense Arwic Slice C	3.487 / 6.044 / 12.432 ms	2.126 / 2.768 / 3.122 ms	26.9 MiB

The capped path improved CPU p95/p99 by 15.8%/16.9% and GPU p95/p99 by 17.4%/20.0%. The uncapped path improved CPU p95/p99 by 13.8%/17.0% and GPU p95/p99 by 22.5%/20.6%. Dense Arwic improved CPU p99 by 12.0% and GPU p99 by 16.8%. Capped GPU p50 rose by 0.134 ms, but every capped GPU tail percentile improved; neither the uncapped nor dense captures repeated that median cost.

Allocation, GC, and probe result

Capture	Process allocation	GC pause	Gen0 / Gen1 / Gen2	Invalid Setup probe exceptions
Capped Slice A	22.61 GB	2.900 s	191 / 159 / 54	4,851
Capped Slice C	10.21 GB	1.368 s	82 / 84 / 26	0
Uncapped Slice A	25.31 GB	2.567 s	278 / 143 / 58	4,659
Uncapped Slice C	14.74 GB	1.325 s	188 / 83 / 23	0
Dense Slice A	5.60 GB	0.623 s	53 / 34 / 14	331
Dense Slice C	2.14 GB	0.286 s	19 / 19 / 7	0

Process allocation fell 54.9% capped, 41.8% uncapped, and 61.9% in dense Arwic. GC pause time fell 52.8%, 48.4%, and 54.1%, respectively. The explicit prepared Setup presence probe eliminated the normal-control-flow ArgumentOutOfRangeException storm without swallowing unexpected failures.

The largest frame-thread allocation fell 77.0% capped and 80.3% uncapped. This slice therefore removed most of the portal decode spike even though the 2026-07-24 audit correctly assigned the remaining publication/retirement work to cost-budgeted streaming Slice E.

Residency interpretation

Both repeated-Caul routes passed the existing warm-return/plateau memory assertion without changing its threshold:

• capped Caul return to plateau: +80.6 MiB working set, +53.8 MiB private;
• uncapped Caul return to plateau: +232.0 MiB working set, +183.7 MiB private.

Handles and threads also returned to their established bands. First-to-final working set is higher than Slice A because Windows includes clean pages from the 27.53 GiB memory-mapped package in process working set. Those pages are discardable file cache, not private heap or retained world ownership. Private memory remained bounded across warm revisits, while entity, animation, particle, mesh-upload, teardown, and ownership invariants passed.

This is a correctness-first package, not the final disk/residency format. Deduplication and compression may reduce its footprint later, but they were deliberately excluded from the byte/field-equivalence cutover.

Architecture closeout

• Production ObjectMeshManager reads only IPreparedAssetSource; it has no live-DAT extraction fallback.
• DatPreparedAssetSource remains explicit tooling/equivalence infrastructure.
• GfxObj, Setup, and EnvCell identities are typed and validated.
• Missing, corrupt, canceled, and loaded reads remain distinct.
• Portal DAT wins the non-allocating preferred-ID lookup.
• Worker preparation and render-thread GL upload ownership remain unchanged.
• Mesh workers stop before the package is unmapped during shutdown.
• Prepared-source probe/read/result counters are exposed in the existing render resource diagnostic record.

Machine-readable, path-free evidence is in 2026-07-24-slice-c-prepared-asset-cutover-report.json. Raw frame histories, counters, reports, screenshots, and logs remain local untracked diagnostic artifacts.