retoor
af080fe68e
- Approval: re-prompt unknown answers (max 3), shell-only affirmative guidance recovery; destructive actions stay strict - GoalVerifier subagent with strict JSON verdicts, bounded follow-up rounds, nonzero exit plus open turn on unverified one-shots - Retrieval eval (Hit@K/MRR/nDCG/Context Precision), FTS cascade with title weighting, query/read event logging, --eval-retrieval CLI - Supervisor caps (8 parallel, 64 records) and scheduler hardening (4 fires/tick, per-schedule lease, stated misfire policy) - Sandbox box resource trio: 2g/2.0/256 at create, best-effort update for existing boxes, rm -f recovery pointer - Research archive: 12 subjects, 667 sources, 27 conclusions; suites 979 + 16 green
52 lines
2.5 KiB
Markdown
52 lines
2.5 KiB
Markdown
# Supervisor Behaviour
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## Metadata
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| Field | Value |
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| Institute | Molodetz Institute — Research & Retrieval Division |
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| Subject | background-work-limits |
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| Document type | Source Dossier |
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| Tier | 1 |
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| Source title | Supervisor Behaviour |
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| Source URL | https://www.erlang.org/doc/design_principles/sup_princ.html |
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| Source publisher / author | Erlang/OTP System Documentation v29.1.2 |
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| Source type | vendor docs |
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| Source date (published) | Unknown — not stated (living documentation page) |
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| Date researched | 2026-10-18 |
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| Researched by | tai (agent), model: Muse Spark, on behalf of retoor |
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| Research method | both |
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| Confidence | High |
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| Status | Active |
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## Summary
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The OTP supervisor reference: children restart by strategy, but restarts are bounded by a maximum intensity (MaxR restarts in MaxT seconds, default 1 in 5), past which the supervisor terminates everything and escalates. Bounding must be structural (a counter with a tripwire), not advisory.
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## Key findings
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- "The supervisors have a built-in mechanism to limit the number of restarts which can occur in a given time interval", specified by `intensity` (MaxR) and `period` (MaxT).
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- "If more than `MaxR` number of restarts occur in the last `MaxT` seconds, the supervisor terminates all the child processes and then itself."
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- "The intention of the restart mechanism is to prevent a situation where a process repeatedly dies for the same reason, only to be restarted again."
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- Defaults are `1` and `5` when not given; escalation goes to the next higher-level supervisor.
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## Pros / strengths
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- Four decades of production supervision distilled into one mechanism; the intensity-plus-period shape is directly portable to any retry or respawn loop.
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- The escalation rule (trip, terminate, let the parent decide) matches tai's loud-failure style better than silent infinite retry.
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## Cons / limitations / caveats
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- Erlang process semantics (cheap processes, real kills) do not transfer to Python threads, which cannot be killed; tai can refuse and abandon but never terminate a stuck worker.
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- No notion of a parallel-worker cap; OTP bounds restarts, not breadth, so the fan-out half comes from the semaphore source instead.
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## Relevance to tai
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Justifies the two bounds tai adopts: a parallel-live cap (breadth) plus no-blind-retry (tai workers and schedules never auto-restart; failures surface as loud results). If tai ever adds worker retry, this source prescribes intensity-plus-period as its shape.
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## Changelog
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| Date | Change |
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| 2026-10-18 | Initial dossier created. |
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