F335 atomic completed-epoch retirement checks
Date: 2026-08-07 UTC
Host: cuda-ke
Kernel: Linux 7.0.0-28-generic x86_64
Python: 3.12.3
MPI: Open MPI 4.1.6 / mpi4py 4.1.1 / MPI 3.1

Static and syntax checks
- ruff touched production/test/evidence Python: pass
- Python bytecode compilation for touched Python: pass
- git diff --check including untracked delivery files: pass
- evidence-directory __pycache__ residue: none

Tests
- distributed/lifecycle/filesystem directed tests: 195 passed, 30 subtests in 15.74 s
- related MPI/distributed/hybrid tests: 312 passed, 38 subtests in 16.62 s
- full warnings-as-errors Python regression: 708 passed, 58 subtests in 96.23 s
- retirement/GC negatives: active symlink, malformed reserved name, retired symlink, invalid limit, and post-rename fsync uncertainty all fail closed

Real MPI post-rename uncertainty and convergence
- ranks and masters/workers: 7 and 2/5
- sealed work epoch: f335 repeated 16 times
- actual MPI transport: true
- actual multi-host: false
- synthetic topology: false
- injected failure point: rank-0 rename visible, parent-directory fsync not performed
- injected worker ACKs before retirement failure: 3/3 + 2/2
- injected return code and elapsed: 72 and 3.6238950230181217 s
- active after injected failure: false
- exact retired roots after injected failure: 1
- matching recovery startup reclaimed roots: 1
- matching recovery worker ACKs: 3/3 + 2/2
- matching recovery return code and elapsed: 0 and 3.7320157941430807 s
- active after matching recovery: false
- exact new retired roots after matching recovery: 1
- prior and new retirement identities differ: true
- content-addressed seed digest and bytes intact: true
- all JSON checks: pass

Mechanism cost
- warm-ups/repetitions per scale: 5/30 interleaved and alternating
- 3 files recursive/retirement median and p95: 2593.562/2721.449 vs 2620.398/2661.56 us
- 3 files median saved and speedup: -26.83600000000024 us and 0.9897588076315124x
- 129 files recursive/retirement median and p95: 3280.4790000000003/3865.488 vs 2638.7405/2732.876 us
- 129 files median saved and speedup: 641.7385000000004 us and 1.2431987912415035x
- 1025 files recursive/retirement median and p95: 9008.330999999998/10274.199 vs 2875.4610000000002/3827.281 us
- 1025 files median saved and speedup: 6132.869999999998 us and 3.1328301792303903x
- raw sample counts: 30+30 at each of three scales
- all samples complete: true

Strict evidence boundaries
- deployment_evidence=false
- remote_power_loss_tested=false
- real_fsync_failure_tested=false
- actual_multi_host=false
- cross_job_lock_exclusion_tested=false
- nfs_server_failover_tested=false
- mpi_rank_repair_tested=false
- network_partition_tested=false
- ulfm_repair_tested=false
- end_to_end_campaign_benchmarked=false
- dse_throughput_benchmarked=false
- solver_or_coverage_uplift_measured=false
- lava_m_campaign_run=false
- GC limit bounds retired roots, not entries or wall time

Repository inventory after F335
- documented feature IDs: F00-F335 (336 total)
- documented SYMCC configuration names: 411
- top-level test files: 246