Power Mode Sequencing and Handshake Robustness: Reports and Metrics

Reports and metrics

Reports and Metrics for Power Mode Sequencing and Handshake Robustness is anchored on Handshake completion success under stress, P99 entry/exit latency per mode, and number of sequencing deadlock or livelock scenarios proven absent.. Convert observations into mechanism-backed and owner-bound actions.

A useful report explains why behavior moved, not only that behavior moved.

Evidence matrix

EVIDENCE MATRIX - Power Mode Sequencing and Handshake Robustness

+-----------------------------+--------------------------------+--------------------------------+---------------------------+
| Evidence                    | Tells you                      | Does not prove                 | Next action               |
+-----------------------------+--------------------------------+--------------------------------+---------------------------+
| transition timeline traces  | first failing LP phase         | complete root-cause ownership  | correlate with intent map |
| UPF-aware assertion logs    | contract violations by phase   | silicon product impact         | map to scenario severity  |
| corruption/X classification | actionable vs noisy failures   | legal transition completeness  | replay key mode corners   |
| save/restore snapshots      | state integrity movement       | isolation correctness          | pair with crossing checks |
| before-after regressions    | mitigation movement quality    | long-tail stability            | run full matrix           |
+-----------------------------+--------------------------------+--------------------------------+---------------------------+

• Track Handshake completion success under stress, P99 entry/exit latency per mode, and number of sequencing deadlock or livelock scenarios proven absent. on representative low-power scenarios.

• Include branch, seed, mode, and configuration metadata in every report.

• Correlate observed symptoms with phase and boundary assumptions.

• Call out contradictory evidence explicitly.

Low-power verification deep dive

Power-state correctness is a protocol contract: legal transitions, robust sequencing, and safe concurrent event handling.

Concept diagram

PST CONTROL LOOP

state request -> legality check -> handshake sequencing -> mode entry -> monitored exit

Metric graph

STATE RISK MIX

illegal transitions     ██████
sequence race bugs      █████
stable mode paths       ████████

Metrics and artifacts to collect

• PST legality matrix

• illegal transition histogram

• entry/exit handshake coverage

• mode sequencing anomaly log

Mini case study

A sporadic low-power failure closed only after proving a wake-versus-thermal race in PMU transition sequencing.

Debug branches

• Validate legal state graph first.

• Stress concurrent control events and asynchronous wakeups.

• Bind fixes to explicit transition and owner contracts.

Senior review question

Ask: what exact low-power transition boundary failed first, and which artifact proves the closure claim reproducibly?

Key takeaways

• Tie each LPV claim to a concrete transition boundary and one proving artifact.

• Prefer minimal reversible fixes with explicit owner and rollback criteria.

Common pitfalls

• Treating power-aware failures as random before boundary classification.

• Waiving X-prop failures before proving impact and root cause.

• Declaring closure without deterministic replay across key modes.

Report interpretation

Read metric movement with phase and boundary context.

A report is actionable only when it isolates first failing transition boundary.