Cutover slice C2: the dormant placement path's per-operation cost was the
recorded activation blocker for routing frame-frequency traffic through
the canonical SetPosition owner (1,880 B/op measured at 4B2, cap 2,048).
Root-cause removal, not a raised cap: the per-operation envelope is now
pooled (bounded 64, reset-at-rent, InPool double-retire guard, cleared on
session reset/dispose and surfaced as a diagnostic ownership count), the
two engine-callback closures became one cached delegate over an explicit
context stack, and the pending-projection head read no longer boxes the
sorted enumerator. Measured 2,032 -> 944 B/op; the regression gate
tightens to 1,536. The residual floor is documented at the gate: ~520 B
inside Core's PhysicsEngine.SetPosition (outside this slice's scope) and
~208 B of sorted-tree node per pending receipt.
Pooling demanded — and received — the full staleness-discipline rework:
every frame holding an operation across a reentrancy point now captures
its never-reissued token and revalidates via fresh lookup
(IsCurrentByToken / token-shaped CancelCore), because a recycled
instance reinstalled at the same key makes every reference-identity
check a tautology. All ~26 sites audited (15 remain reference-based with
per-site no-reentrancy proofs); CommitCanonical's post-callback reads
are hoisted stack locals mirroring retail's savedTransientState pattern
(handle_all_collisions bits, pseudo-C 283952), its bookkeeping writes
are token-gated, and the settle path stays deliberately identity-
agnostic because retail's SetPositionInternal runs its physical settle
unconditionally even for displaced operations.
Reviewed: retail-conformance PASS + architecture/adversarial PASS after
two fix rounds (the ground-edge recycle window, the pool's cross-reset
retention, the class-wide tautology, a self-found snapshot-reference
iteration hazard). Runtime 927/927; complete Release solution 10,722
passed / 4 intentional skips; budget test green at the tightened gate.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Cutover slice C0 (docs/plans/2026-08-02-placement-cutover.md): the seam
work that lets C3 flip hosts onto a complete receipt stream instead of
growing one mid-cutover. The executor's Released exit now publishes an
acknowledge-only ExecutorCompleted receipt through the one placement
projection stream — registered before observer dispatch, correlated to
the full execution receipt, reaped exactly once on acknowledgement/
discard/session-clear, and counted in the convergence ledger. All three
production placement sinks acknowledge-and-ignore the new kind via early
returns proven behavior-preserving for every existing kind; without them
the first such receipt at cutover would permanently wedge the exact-head
FIFO behind sinks that return false. Provably inert today: the publisher
has no production caller.
Execute's live inputs now derive from Runtime's own owners bound at
GameRuntime construction: UsePositionFromServer is retail's exact
autonomy_level != 2 (CommandInterpreter::UsePositionFromServer
0x006B3B40, startup-only knob), and PlayerDistance uses the live movement
controller's position with a null-safe fallback to the caller struct —
never a fabricated origin. TryPrepareAndSubmitAuthoredPlacement chains
the prepared-collision Setup read through PrepareMover to submission with
zero validation-semantics changes. TryCommitParent and CommitWithdrawal
gain the sibling cancellation flow (residence + ordinary placement
family); TryCommitParent deliberately omits LeaveWorld — retail's
set_parent performs its single gated leave_world (0x00515A90) and a
second would have no counterpart.
Not fully dormant: the two cancellation fixes change Runtime paths
production already calls (today as no-op-adjacent hardening, since
nothing upstream begins a residence yet); everything else is reachable
only by tests. Reviewed: retail-conformance PASS + architecture/
adversarial PASS after one fix round (sink wedge, completion-receipt
lifecycle, null-controller distance). Runtime 921/921; complete Release
solution 10,716 passed / 4 intentional skips.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
