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Group `.claude/` ignores per-skill instead of a flat list: `ai.skillz` symlinks, `/open-wkt`, `/code-review-changes`, `/pr-msg`, `/commit-msg`. Add missing symlink entries (`yt-url-lookup` -> `resolve-conflicts`, `inter-skill-review`). Drop stale `Claude worktrees` section (already covered by `.claude/wkts/`). (this commit msg was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
New "Inspect last failures" section reads the pytest `lastfailed` cache JSON directly — instant, no collection overhead, and filters to `tests/`-prefixed entries to avoid stale junk paths. Also, - add `jq` tool permission for `.pytest_cache/` files (this commit msg was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Rework section 3 from a worktree-only check into a structured 3-step flow: detect active venv, interpret results (Case A: active, B: none, C: worktree), then run import + collection checks. Deats, - Case B prompts via `AskUserQuestion` when no venv is detected, offering `uv sync` or manual activate - add `uv run` fallback section for envs where venv activation isn't practical - new allowed-tools: `uv run python`, `uv run pytest`, `uv pip show`, `AskUserQuestion` (this commit msg was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Land the scaffolding for a future sub-interpreter (PEP 734 `concurrent.interpreters`) actor spawn backend per issue #379. The spawn flow itself is not yet implemented; `subint_proc()` raises a placeholder `NotImplementedError` pointing at the tracking issue — this commit only wires up the registry, the py-version gate, and the harness. Deats, - bump `pyproject.toml` `requires-python` to `>=3.12, <3.15` and list the `3.14` classifier — the new stdlib `concurrent.interpreters` module only ships on 3.14 - extend `SpawnMethodKey = Literal[..., 'subint']` - `try_set_start_method('subint')` grows a new `match` arm that feature-detects the stdlib module and raises `RuntimeError` with a clear banner on py<3.14 - `_methods` registers the new `subint_proc()` via the same bottom-of-module late-import pattern used for `._trio` / `._mp` Also, - new `tractor/spawn/_subint.py` — top-level `try: from concurrent import interpreters` guards `_has_subints: bool`; `subint_proc()` signature mirrors `trio_proc`/`mp_proc` so the Phase B.2 impl can drop in without touching the registry - re-add `import sys` to `_spawn.py` (needed for the py-version msg in the gate-error) - `_testing.pytest.pytest_configure` wraps `try_set_start_method()` in a `pytest.UsageError` handler so `--spawn-backend=subint` on py<3.14 prints a clean banner instead of a traceback (this patch was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Since we're devving subints we require the 3.14+ stdlib API
and a couple compiled libs don't support it yet, namely:
- `cffi`, which we're only using for the `.ipc._linux` eventfd
stuff (now factored into `hotbaud` anyway).
- `greenback`, which requires `greenlet` which doesn't seem to be
wheeled yet
* on nixos the sdist build was failing due to lack of `g++` which
i don't care to figure out rn since we don't need `.devx` stuff
immediately for this subints prototype.
* [ ] we still need to adjust any dependent suites to skip.
Adjust `test_ringbuf` to skip on import failure.
Also project wide,
- pin us to py 3.13+ in prep for last-2-minor-version policy.
- drop `msgspec>=0.20.0`, the first release with py3.14 support.
Replace the B.1 scaffold stub w/ a working spawn flow driving PEP 734 sub-interpreters on dedicated OS threads. Deats, - use private `_interpreters` C mod (not the public `concurrent.interpreters` API) to get `'legacy'` subint config — avoids PEP 684 C-ext compat issues w/ `msgspec` and other deps missing the `Py_mod_multiple_interpreters` slot - bootstrap subint via code-string calling new `_actor_child_main()` from `_child.py` (shared entry for both CLI and subint backends) - drive subint lifetime on an OS thread using `trio.to_thread.run_sync(_interpreters.exec, ..)` - full supervision lifecycle mirrors `trio_proc`: `ipc_server.wait_for_peer()` → send `SpawnSpec` → yield `Portal` via `task_status.started()` - graceful shutdown awaits the subint's inner `trio.run()` completing; cancel path sends `portal.cancel_actor()` then waits for thread join before `_interpreters.destroy()` Also, - extract `_actor_child_main()` from `_child.py` `__main__` block as callable entry shape bc the subint needs it for code-string bootstrap - add `"subint"` to the `_runtime.py` spawn-method check so child accepts `SpawnSpec` over IPC Prompt-IO: ai/prompt-io/claude/20260417T124437Z_5cd6df5_prompt_io.md (this patch was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Expand the comment block above the `_interpreters` import explaining *why* we use the private C mod over `concurrent.interpreters`: the public API only exposes PEP 734's `'isolated'` config which breaks `msgspec` (missing PEP 684 slot). Add reference links to PEP 734, PEP 684, cpython sources, and the msgspec upstream tracker (jcrist/msgspec#563). Also, - update error msgs in both `_spawn.py` and `_subint.py` to say "3.13+" (matching the actual `_interpreters` availability) instead of "3.14+". - tweak the mod docstring to reflect py3.13+ availability via the private C module. Review: PR #444 (copilot-pull-request-reviewer) #444 (this patch was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
`trio.to_thread.run_sync(_interpreters.exec, ...)` runs `exec()` on a cached worker thread — and when that thread is returned to the cache after the subint's `trio.run()` exits, CPython still keeps the subint's tstate attached to the (now idle) worker. Result: the teardown `_interpreters.destroy(interp_id)` in the `finally` block can block the parent's trio loop indefinitely, waiting for a tstate release that only happens when the worker either picks up a new job or exits. Manifested as intermittent mid-suite hangs under `--spawn-backend=subint` — caught by a `faulthandler.dump_traceback_later()` showing the main thread stuck in `_interpreters.destroy()` at `_subint.py:293` with only an idle trio-cache worker as the other live thread. Deats, - drive the subint on a plain `threading.Thread` (not `trio.to_thread`) so the OS thread truly exits after `_interpreters.exec()` returns, releasing tstate and unblocking destroy - signal `subint_exited.set()` back to the parent trio loop from the driver thread via `trio.from_thread.run_sync(..., trio_token=...)` — capture the token at `subint_proc` entry - swallow `trio.RunFinishedError` in that signal path for the case where parent trio has already exited (proc teardown) - in the teardown `finally`, off-load the sync `driver_thread.join()` to `trio.to_thread.run_sync` (cache thread w/ no subint tstate → safe) so we actually wait for the driver to exit before `_interpreters.destroy()` (this patch was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Log the `claude-opus-4-7` session that produced the `_subint.py` dedicated-thread fix (`26fb8206`). Substantive bc the patch was entirely AI-generated; raw log also preserves the CPython-internals research informing Phase B.3 hard-kill work. Prompt-IO: ai/prompt-io/claude/20260418T042526Z_26fb820_prompt_io.md (this commit msg was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Unbounded `trio.CancelScope(shield=True)` at the soft-kill and thread-join sites can wedge the parent trio loop indefinitely when a stuck subint ignores portal-cancel (e.g. bc the IPC channel is already broken). Deats, - add `_HARD_KILL_TIMEOUT` (3s) module-level const - wrap both shield sites with `trio.move_on_after()` so we abandon a stuck subint after the deadline - flip driver thread to `daemon=True` so proc-exit also isn't blocked by a wedged subint - pass `abandon_on_cancel=True` to `trio.to_thread.run_sync(driver_thread.join)` — load-bearing for `move_on_after` to actually fire - log warnings when either timeout triggers - improve `InterpreterError` log msg to explain the abandoned-thread scenario (this patch was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Bottle up the diagnostic primitives that actually cracked the silent mid-suite hangs in the `subint` spawn-backend bringup (issue there" session has them on the shelf instead of reinventing from scratch. Deats, - `dump_on_hang(seconds, *, path)` — context manager wrapping `faulthandler.dump_traceback_later()`. Critical gotcha baked in: dumps go to a *file*, not `sys.stderr`, bc pytest's stderr capture silently eats the output and you can spend an hour convinced you're looking at the wrong thing - `track_resource_deltas(label, *, writer)` — context manager logging per-block `(threading.active_count(), len(_interpreters.list_all()))` deltas; quickly rules out leak-accumulation theories when a suite progressively worsens (if counts don't grow, it's not a leak, look for a race on shared cleanup instead) - `resource_delta_fixture(*, autouse, writer)` — factory returning a `pytest` fixture wrapping `track_resource_deltas` per-test; opt in by importing into a `conftest.py`. Kept as a factory (not a bare fixture) so callers own `autouse` / `writer` wiring Also, - export the three names from `tractor.devx` - dep-free on py<3.13 (swallows `ImportError` for `_interpreters`) - link back to the provenance in the module docstring (issue #379 / commit `26fb820`) (this patch was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
The private `_interpreters` C module ships since 3.13, but that vintage
wedges under our `threading.Thread` + multi-trio usage pattern
—> `_interpreters.exec()` silently never makes progress. 3.14 fixes it.
So gate on the presence of the public `concurrent.interpreters` wrapper
(3.14+ only) even tho we still call into the private module at runtime.
Deats,
- `try_set_start_method('subint')` error msg + `_subint` module
docstring/comments rewritten to document the 3.14 floor and why 3.13
can't work.
- `_subint._has_subints` gate now imports `concurrent.interpreters` (not
`_interpreters`) as the version sentinel.
Also, reshuffle `pyproject.toml` deps into
per-python-version `[tool.uv.dependency-groups]`:
- `subints` group: `msgspec>=0.21.0`, py>=3.14
- `eventfd` group: `cffi>=1.17.1`, py>=3.13,<3.14
- `sync_pause` group: `greenback`, py>=3.13,<3.14
(was in `devx`; moved out bc no 3.14 yet)
Bump top-level `msgspec>=0.20.0` too.
(this commit msg was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
Lock in the escape-hatch machinery added to `tractor.spawn._subint` during the Phase B.2/B.3 bringup (issue #379) so future stdlib regressions or our own refactors don't silently re-introduce the mid-suite hangs. Deats, - `test_subint_happy_teardown`: baseline — spawn a subactor, one portal RPC, clean teardown. If this breaks, something's wrong unrelated to the hard-kill shields. - `test_subint_non_checkpointing_child`: cancel a subactor stuck in a non-checkpointing Python loop (`threading.Event.wait()` releases the GIL but never inserts a trio checkpoint). Validates the bounded-shield + daemon-driver-thread combo abandons the thread after `_HARD_KILL_TIMEOUT`. Every test is wrapped in `trio.fail_after()` for a deterministic per-test wall-clock ceiling (an unbounded audit would defeat itself) and arms `tractor.devx.dump_on_hang()` so a hang captures a stack dump — pytest's stderr capture swallows `faulthandler` output by default. Gated via `pytest.importorskip('concurrent.interpreters')` and a module-level skip when `--spawn-backend` isn't `'subint'`. (this patch was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Classify and write up the two distinct hang modes hit during Phase B subint bringup (issue #379) so future triage doesn't re-derive them from scratch. Deats, two new `ai/conc-anal/` docs, - `subint_sigint_starvation_issue.md`: abandoned legacy-subint thread + shared GIL → main trio loop starves → signal-wakeup-fd pipe fills → `SIGINT` silently dropped (`strace` shows `write() = EAGAIN` on the wakeup-fd). Un- Ctrl-C-able. Structurally a CPython limit; blocked on `msgspec` PEP 684 (jcrist/msgspec#563) - `subint_cancel_delivery_hang_issue.md`: parent-side trio task parks on an orphaned IPC channel after subint teardown — no clean EOF delivered to the waiting receive. Ctrl-C-able (main loop iterates fine); OUR bug to fix. Candidate fix: explicit parent-side channel abort in `subint_proc`'s hard-kill teardown Cross-link the docs from their test reproducers, - `test_stale_entry_is_deleted` (→ starvation class): wrap `trio.run(main)` in `dump_on_hang(seconds=20)` so a future regression captures a stack dump. Kept un- skipped so the dump file is inspectable - `test_subint_non_checkpointing_child` (→ delivery class): extend docstring with a "KNOWN ISSUE" block pointing at the analysis (this patch was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Log the `claude-opus-4-7` collab that produced `e92e3cd2` ("Doc `subint`
backend hang classes + arm `dump_on_hang`"). Substantive bc the two new
`ai/conc-anal/` docs were jointly authored — user framed the two-class
split + set candidate-fix ordering for the class-2 (Ctrl-C-able) hang;
claude drafted the prose and the test-side cross-linking comments.
`.raw.md` is in diff-ref mode — per-file pointers via `git diff
e92e3cd~1..e92e3cd -- <path>` rather than re-embedding content that
already lives in `git log -p`.
Prompt-IO: ai/prompt-io/claude/20260420T192739Z_5e8cd8b2_prompt_io.md
(this commit msg was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
Add a hard process-level wall-clock bound on the two known-hanging subint-backend tests so an unattended suite run can't wedge indefinitely in either of the hang classes doc'd in `ai/conc-anal/`. Deats, - New `testing` dep: `pytest-timeout>=2.3`. - `test_stale_entry_is_deleted`: `@pytest.mark.timeout(3, method='thread')`. The `method='thread'` choice is deliberate — `method='signal'` routes via `SIGALRM` which is starved by the same GIL-hostage path that drops `SIGINT` (see `subint_sigint_starvation_issue.md`), so it'd never actually fire in the starvation case. - `test_subint_non_checkpointing_child`: same decorator, same reasoning (defense-in-depth over the inner `trio.fail_after(15)`). At timeout, `pytest-timeout` hard-kills the pytest process itself — that's the intended behavior here; the alternative is the suite never returning. (this commit msg was generated in some part by [`claude-code`][claude-code-gh]) [claude-code-gh]: https://github.com/anthropics/claude-code
Add two more tests to the catalog in
`conc-anal/subint_sigint_starvation_issue.md` — same
signal-wakeup-fd-saturation fingerprint (abandoned legacy-subint driver
threads → shared-GIL starvation → `write() = EAGAIN` on the wakeup pipe
→ silent SIGINT drop), different load patterns.
Deats,
- `test_cancel_while_childs_child_in_sync_sleep[subint-False]`: nested
actor-tree + sync-sleeping grandchild. Under `trio`/`mp_*` the "zombie
reaper" is a subproc `SIGKILL`; no equivalent exists under subint, so
the grandchild persists in its abandoned driver thread. Often only
manifests under full-suite runs (earlier tests seed the
abandoned-thread pool).
- `test_multierror_fast_nursery[subint-25-0.5]`: 25 concurrent subactors
all go through teardown on the multierror. Bounded hard-kills run in
parallel — so the total budget is ~3s, not 3s × 25. Leaves 25
abandoned driver threads simultaneously alive, an extreme pressure
multiplier. `strace` shows several successful `write(16, "\2", 1) = 1`
(GIL round-robin IS giving main brief slices) before finally
saturating with `EAGAIN`.
Also include a `pstree -snapt <pid>` capture showing
16+ live `{subint-driver[<interp_id>}` threads at the
moment of hang — the direct GIL-contender population.
(this commit msg was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
A reusable `@pytest.mark.skipon_spawn_backend( '<backend>' [, ...],
reason='...')` marker for backend-specific known-hang / -borked cases
— avoids scattering `@pytest.mark.skipif(lambda ...)` branches across
tests that misbehave under a particular `--spawn-backend`.
Deats,
- `pytest_configure()` registers the marker via
`addinivalue_line('markers', ...)`.
- New `pytest_collection_modifyitems()` hook walks
each collected item with `item.iter_markers(
name='skipon_spawn_backend')`, checks whether the
active `--spawn-backend` appears in `mark.args`, and
if so injects a concrete `pytest.mark.skip(
reason=...)`. `iter_markers()` makes the decorator
work at function, class, or module (`pytestmark =
[...]`) scope transparently.
- First matching mark wins; default reason is
`f'Borked on --spawn-backend={backend!r}'` if the
caller doesn't supply one.
Also, tighten type annotations on nearby `pytest`
integration points — `pytest_configure`, `debug_mode`,
`spawn_backend`, `tpt_protos`, `tpt_proto` — now taking
typed `pytest.Config` / `pytest.FixtureRequest` params.
(this commit msg was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
Adopt the `@pytest.mark.skipon_spawn_backend('subint',
reason=...)` marker (a617b52) across the suites
reproducing the `subint` GIL-contention / starvation
hang classes doc'd in `ai/conc-anal/subint_*_issue.md`.
Deats,
- Module-level `pytestmark` on full-file-hanging suites:
- `tests/test_cancellation.py`
- `tests/test_inter_peer_cancellation.py`
- `tests/test_pubsub.py`
- `tests/test_shm.py`
- Per-test decorator where only one test in the file
hangs:
- `tests/discovery/test_registrar.py
::test_stale_entry_is_deleted` — replaces the
inline `if start_method == 'subint': pytest.skip`
branch with a declarative skip.
- `tests/test_subint_cancellation.py
::test_subint_non_checkpointing_child`.
- A few per-test decorators are left commented-in-
place as breadcrumbs for later finer-grained unskips.
Also, some nearby tidying in the affected files:
- Annotate loose fixture / test params
(`pytest.FixtureRequest`, `str`, `tuple`, `bool`) in
`tests/conftest.py`, `tests/devx/conftest.py`, and
`tests/test_cancellation.py`.
- Normalize `"""..."""` → `'''...'''` docstrings per
repo convention on a few touched tests.
- Add `timeout=6` / `timeout=10` to
`@tractor_test(...)` on `test_cancel_infinite_streamer`
and `test_some_cancels_all`.
- Drop redundant `spawn_backend` param from
`test_cancel_via_SIGINT`; use `start_method` in the
`'mp' in ...` check instead.
(this commit msg was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
goodboy
changed the title
goodboy
changed the title
goodboy
commented
Apr 24, 2026
| # https://peps.python.org/pep-0684/ | ||
| # - stdlib docs (3.14+): | ||
| # https://docs.python.org/3.14/library/concurrent.interpreters.html | ||
| # - CPython public wrapper source (`Lib/concurrent/interpreters/`): |
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we're missing a link to the older pep-554 here?
goodboy
commented
Apr 24, 2026
| from trio import TaskStatus | ||
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| # NOTE: we reach into the *private* `_interpreters` C module |
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Reason for pinning to the legacy API..
goodboy
commented
Apr 24, 2026
| @@ -0,0 +1,350 @@ | |||
| # `subint` backend: abandoned-subint thread can wedge main trio event loop (Ctrl-C unresponsive) | |||
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The full reason we need a GIL per subint..
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