Physical AI Supervisor Node Replacement 022 - Raw Research Artifact

Generated at: 2026-07-09T13:24:21Z Classification: Experimental runtime path validation

Purpose

Experiment 022 validates the SQL-backed Action-Outcome supervisor under a node-replacement shaped sequence: node A processes work, its lease expires, node B takes over, stale node A is fenced, and restarted node B finishes the proposal stream.

Summary

Metric	Value
Total proposals	3
Final commit rows	3
Final decision rows	3
Final evidence rows	3
Stale node A batch proposals	0
Stale node A processed rows	0
Final owner epoch	2

Ownership Handoff

Step	Owner	Epoch	Processed	Duplicate Skips	Result
Initial pass	node-a	1	1	0	first proposal committed
Replacement pass	node-b	2	1	>=1	expired lease taken over
Stale probe	node-a	1	0	0	fenced / idle
Restarted owner	node-b	2	1	>=1	final proposal committed

Acceptance

Criterion	Status
node A first pass commits one proposal	pass
expired lease takeover promotes node B	pass
stale node A processes no work after takeover	pass
restarted node B completes remaining proposal	pass
commit rows converge to 3	pass
decision rows converge to 3	pass
evidence rows converge to 3	pass
commit proposal ids remain unique	pass

Verification

ninja -C build -j$(nproc) zepto_tests

./build/tests/zepto_tests \
  --gtest_filter='ActionOutcomeSqlAdapterTest.WorkerLeaseRollingRestartNodeReplacementFencesStaleOwnerAndConverges' \
  --gtest_brief=1

Result: pass, 1/1 focused test.

Broader gates:

• x86_64 CTest: pass, 1712/1712.
• aarch64 stage 8 CTest: pass, 1712/1712.
• Live S3 opt-in smoke: pass, 2/2; temporary bucket cleanup verified gone.

Interpretation

The supervisor-specific SQL lease is sufficient to fence a stale owner in the validated shadow runtime flow. This closes the operational node-replacement validation item for controlled pilots, while preserving the documented limit: the SQL lease is not a general consensus election protocol.