ai/prompt-io/opencode/20260821T023537Z_ae6f2ac3_prompt_io.md

@@ -1,65 +0,0 @@
----
-model: openai/gpt-5.6-sol
-service: opencode
-session: 76c5d31c-5a2f-4503-9b16-410ee7f4fab3
-timestamp: 2026-08-21T02:35:37Z
-git_ref: ae6f2ac3
-scope: code
-substantive: true
-raw_file: 20260821T023537Z_ae6f2ac3_prompt_io.raw.md
----
-
-## Prompt
-
-Simplify bounded actor cancellation by passing an explicit absolute
-deadline from `Portal.cancel_actor()` through `_run_from_ns()`,
-`Actor.start_remote_task()`, and `Channel.send()` into
-`MsgpackTransport.send()`. Avoid a `ContextVar`, watcher tasks, shared
-status, coalescing, and waiter state. After tracing the current
-`Start -> StartAck -> CancelAck` transaction, rename the local result to
-`cancel_ack_received`, document its exact semantics, and link a focused
-follow-up for a dedicated `Cancel -> CancelAck` protocol.
-
-## Response summary
-
-Threaded one absolute Trio deadline through the existing private
-actor-cancel RPC path. The transport retains complete-frame shielding
-for ordinary sends, while a cancel-control send that overruns its
-deadline force-closes the potentially corrupted stream before releasing
-the send lock. The outer actor-cancel scope uses the same deadline for
-ack waiting and redelivers pending caller cancellation afterward.
-
-Renamed the completion flag to `cancel_ack_received` and documented that
-the current private call consumes `StartAck`, then receives a real
-`CancelAck` after `Actor.cancel()` completes; this does not establish
-that the OS process exited. Added a source TODO linking issue #506 for
-the future first-class `Cancel -> CancelAck` transaction.
-
-Focused transport and actor-cancel verification passed all four tests.
-
-## Files changed
-
-- `tractor/runtime/_portal.py` - own the absolute deadline, accurately
-  record ack receipt, and link the dedicated cancellation protocol.
-- `tractor/runtime/_runtime.py` - forward the optional deadline for the
-  exact private `Start` publication.
-- `tractor/ipc/_chan.py` - pass the operation-specific deadline to the
-  transport without changing ordinary sends.
-- `tractor/ipc/_transport.py` - bound the shielded frame publication and
-  close a partial-frame stream before unlocking it.
-- `tests/ipc/test_each_tpt.py` - cover deadline expiry after a partial
-  frame prefix reaches the stream.
-- `tests/test_to_actor.py` - prove actor-cancel publication and ack
-  waiting share one absolute timeout budget.
-
-## Human edits
-
-The human rejected the initial watcher-task, shared `_SendStatus`, cancel
-coalescing, and per-waiter design as unnecessary complexity. They also
-rejected `ContextVar` propagation in favor of explicit functional
-threading, selected a single absolute deadline for publication and ack
-waiting, and required item 2 to remain separate from the item-3 child
-reaping work. After reviewing the result, they requested the precise
-`cancel_ack_received` name, a detailed protocol-trace comment, a focused
-follow-up issue, and a linked source TODO. No direct source-line edits
-were made by the human.

ai/prompt-io/opencode/20260821T023537Z_ae6f2ac3_prompt_io.raw.md

@@ -1,41 +0,0 @@
----
-model: openai/gpt-5.6-sol
-service: opencode
-timestamp: 2026-08-21T02:35:37Z
-git_ref: ae6f2ac3
-diff_cmd: git diff HEAD~1..HEAD
----
-
-Replace the actor-cancel timeout watcher/status experiment with one
-explicit absolute deadline threaded through the existing private call
-path. Do not use a `ContextVar`, shared result state, waiter
-coalescing, or polling tasks.
-
-> `git diff HEAD~1..HEAD -- tractor/runtime/_portal.py`
-
-`Portal.cancel_actor()` computes one absolute deadline and uses it for
-both `Start` frame publication and the subsequent cancel-ack wait.
-
-> `git diff HEAD~1..HEAD -- tractor/runtime/_runtime.py`
-
-> `git diff HEAD~1..HEAD -- tractor/ipc/_chan.py`
-
-The private RPC path forwards the operation-specific deadline. Lower
-layers preserve the ordinary infinite-deadline call shape.
-
-> `git diff HEAD~1..HEAD -- tractor/ipc/_transport.py`
-
-`MsgpackTransport.send()` applies the deadline inside its complete-frame
-shield. If the deadline expires after partial publication, it closes
-the unusable stream before releasing the send lock.
-
-> `git diff HEAD~1..HEAD -- tests/ipc/test_each_tpt.py`
-
-> `git diff HEAD~1..HEAD -- tests/test_to_actor.py`
-
-Focused regressions prove a partial-frame timeout closes the stream and
-that actor-cancel publication and acknowledgement share one budget.
-
-The implementation removes the earlier `_SendStatus`, watcher task,
-coalescing, shared cancel result, and per-waiter state. Four focused
-transport and actor-cancel tests pass.

ai/prompt-io/opencode/20260821T040803Z_3c1bbe73_prompt_io.md

@@ -1,57 +0,0 @@
----
-model: openai/gpt-5.6-sol
-service: opencode
-session: 76c5d31c-5a2f-4503-9b16-410ee7f4fab3
-timestamp: 2026-08-21T04:08:03Z
-git_ref: 3c1bbe73
-scope: code
-substantive: true
-raw_file: 20260821T040803Z_3c1bbe73_prompt_io.raw.md
----
-
-## Prompt
-
-Continue PR #481 review cleanup one item at a time. Compare the
-remaining child-registration/reaping experiment against PR #484,
-identify the next valid behavior, and generate an exact commit plan for
-that boundary without committing automatically.
-
-## Response summary
-
-Separated late-child admission from the broader bounded-reap rewrite.
-Added one synchronous `ActorNursery._register_child()` publication step
-that stores the child and its reap events before sampling nursery
-cancellation. This closes both scheduler orderings around
-`ActorNursery.cancel()`'s child snapshot.
-
-The MP backend registers immediately before synchronous process startup
-and refuses to start when cancellation already owns the child. The Trio
-backend registers immediately after `open_process()` and kills that
-already-created process when registration observes cancellation. An
-early `start_actor()` guard rejects calls begun after cancellation is
-already visible.
-
-Deterministic tests cover the nursery registration ordering and the MP
-no-start invariant. Comparison with PR #484 confirmed that its retained
-generic nursery/backends do not close this race.
-
-## Files changed
-
-- `tractor/runtime/_supervise.py` - atomically publish child ownership
-  and reject actor starts after nursery cancellation.
-- `tractor/spawn/_mp.py` - register before synchronous process startup
-  and abort a cancellation-owned child.
-- `tractor/spawn/_trio.py` - register immediately after process creation,
-  kill a cancellation-owned child, and remove its stale unused import.
-- `tests/test_to_actor.py` - cover late registration and MP startup
-  suppression.
-
-## Human edits
-
-The human required review extras to be handled one item and one
-behavioral commit at a time, with each item compared against PR #484
-before acceptance. That direction split this late-registration fix from
-the original broad experiment's bounded post-ack reaping,
-`ActorNursery.cancel()` hard-reap rewrite, and debugger/error behavior.
-The human accepted the narrower late-registration boundary by requesting
-its commit plan. No direct source-line edits were made by the human.

ai/prompt-io/opencode/20260821T040803Z_3c1bbe73_prompt_io.raw.md

@@ -1,48 +0,0 @@
----
-model: openai/gpt-5.6-sol
-service: opencode
-timestamp: 2026-08-21T04:08:03Z
-git_ref: 3c1bbe73
-diff_cmd: git diff HEAD~1..HEAD
----
-
-Compare the remaining child-registration and reaping experiment with
-PR #484, then identify the next review item without changing code.
-
-The next item is the late-child admission race. A spawn can pass
-`ActorNursery.start_actor()`'s early cancellation check, then be absent
-from `ActorNursery.cancel()`'s child snapshot and register afterward.
-The existing reap-request latch releases its monitor but does not send
-runtime cancellation, so the monitor can wait forever for a still-live
-process.
-
-> `git diff HEAD~1..HEAD -- tractor/runtime/_supervise.py`
-
-`ActorNursery._register_child()` publishes the child, installs its reap
-events, and samples `ActorNursery._cancel_called` without a checkpoint.
-The two scheduler orderings are then complete: registration first puts
-the child in the cancel snapshot, while cancellation first makes the
-backend abort the late registration.
-
-> `git diff HEAD~1..HEAD -- tractor/spawn/_mp.py`
-
-The multiprocessing backend registers immediately before `proc.start()`
-and refuses to start a process already owned by nursery cancellation.
-There is no Trio checkpoint between registration and process startup.
-
-> `git diff HEAD~1..HEAD -- tractor/spawn/_trio.py`
-
-The Trio backend registers immediately after `open_process()` and kills
-the newly opened process if cancellation won the registration race. Its
-stale unused `get_runtime_vars` import is removed so the touched module
-remains lint-clean.
-
-> `git diff HEAD~1..HEAD -- tests/test_to_actor.py`
-
-Deterministic regressions prove late registration observes cancellation
-and that the MP backend never starts a process after cancellation owns
-its registration.
-
-PR #484 retains the affected generic nursery and spawn-backend paths and
-does not close this race. Keep this fix in PR #481 as its own commit;
-review bounded post-`CancelAck` reaping separately.

docs/api/core.rst

@@ -54,16 +54,15 @@ One-shot task actors
 
 .. note::
 
-   Without ``portal=``, :func:`tractor.to_actor.run` (parlance of
+   :func:`tractor.to_actor.run` (parlance of
-   ``trio.to_thread.run_sync()`` and friends) is the convenience
+   ``trio.to_thread.run_sync()`` and friends) is the
-   one-shot: spawn, run one task, block on its result and reap. It
+   *convenience* one-shot — spawn, run a single task, block on
-   combines :meth:`ActorNursery.start_actor`, a linked
+   its result, reap — built entirely on
-   :meth:`Portal.open_context` call and per-child reaping. With
+   :meth:`ActorNursery.start_actor`, a linked
-   ``portal=`` it owns only the linked task and leaves the existing
+    :meth:`Portal.open_context` call and per-child cancellation/reaping,
-   actor's lifetime to the portal owner; that actor must expose both
+    so don't design around it as the core model. It supersedes the
-   the target module and ``tractor.to_actor.MODULE``. It supersedes
+    legacy, non-blocking ``ActorNursery.run_in_actor()`` retained only
-   the legacy, non-blocking ``ActorNursery.run_in_actor()`` retained
+    for compatibility until its removal in PR #484.
-   only for compatibility until its removal in PR #484.
 
 .. deprecated:: 0.1.0a6
 

docs/guide/clustering.rst

@@ -62,10 +62,7 @@ one kwarg away,
 .. code:: python
 
     async with tractor.open_actor_cluster(
-        modules=[
+        modules=['mylib.workers'],
-            'mylib.workers',
-            tractor.to_actor.MODULE,
-        ],
         count=4,
         names=['scout', 'miner', 'smelter', 'smith'],
         debug_mode=True,    # whole-fleet crash-to-REPL
@@ -74,11 +71,9 @@ one kwarg away,
 
 From here the composition patterns are the usual ``tractor`` fare:
 ``portal.run()`` for bare one-shot RPCs (as in the demo),
-``tractor.to_actor.run(..., portal=portal)`` for cancellation-linked
+``tractor.to_actor.run(..., portal=portal)`` for linked one-shot calls,
-one-shot tasks in an existing worker (include
+or — for a persistent bidirectional dialog per worker — concurrently
-``tractor.to_actor.MODULE`` in ``modules``; the cluster still owns
+enter N ``portal.open_context()`` blocks with
-the worker's lifetime), or — for a persistent bidirectional dialog
-per worker — concurrently enter N ``portal.open_context()`` blocks with
 ``tractor.trionics.gather_contexts()``; see :doc:`/guide/context`
 for that whole layer.
 

docs/guide/context.rst

@@ -15,12 +15,12 @@ a single `structured concurrency`_ (SC) scope over IPC.
    :alt: sequence diagram of the context handshake msg flow
 
 Pretty much everything else is (or is slated to be) built on this
-one primitive: ``tractor.to_actor.run()`` uses it for a linked
+one primitive: ``tractor.to_actor.run()`` is a convenience for
-one-shot task, spawning and reaping an actor only when no ``portal=``
+"spawn, run the lone task, await the result, tear down"; plain
-is supplied; plain ``Portal.run()`` RPC is planned to be
+``Portal.run()`` RPC is planned to be re-implemented on top of it;
-re-implemented on top of it; the multi-process debugger's tree-wide
+the multi-process debugger's tree-wide REPL lock rides one. Grok
-REPL lock rides one. Grok this page and the rest of the library reads
+this page and the rest of the library reads as convenience
-as convenience wrappers B)
+wrappers B)
 
 The endpoint contract
 ---------------------

docs/guide/rpc.rst

@@ -82,9 +82,10 @@ don't build your app on it.
 
 One-shot subactors: ``to_actor.run()``
 --------------------------------------
-When the call should own a fresh subactor whose entire job is one
+When a subactor's *entire job* is a single function call, skip
-function call, :func:`tractor.to_actor.run` spawns it, runs the task,
+the portal plumbing with :func:`tractor.to_actor.run`: spawn,
-returns its result and reaps the process — all in one blocking call:
+run the lone task, return its result and reap the process — all
+in one blocking call:
 
 .. code:: python
 
@@ -100,37 +101,16 @@ Semantics worth knowing:
 - it blocks until the remote task returns, re-raising any
   remote error in the usual boxed form right in the calling
   task.
-- placement also determines process ownership: ``an=`` spawns and
+- "placement" is composable: ``an=`` spawns from an existing
-  reaps a fresh child in an existing actor nursery, while passing
+  actor-nursery, ``portal=`` reuses an already-running actor
-  neither does the same in a private call-scoped nursery (booting
+  (no spawn/reap, just a linked
-  the runtime if needed). ``portal=`` instead runs one linked task
+  :meth:`~tractor.Portal.open_context` call; see the
-  in an existing actor; it neither spawns nor reaps that actor, so
+  :doc:`context guide </guide/context>`), and passing neither
-  the portal's owner remains responsible for its lifetime.
+  opens a private call-scoped nursery (booting the runtime if needed).
 - concurrency composes the plain ``trio`` way: schedule
   multiple ``run()`` calls into a local task nursery (see
   ``examples/parallelism/to_actor_one_shots.py``).
 
-A reused actor must expose both the target module and the
-``to_actor`` context trampoline:
-
-.. code:: python
-
-    async with tractor.open_nursery() as an:
-        portal = await an.start_actor(
-            'worker',
-            enable_modules=[
-                __name__,
-                tractor.to_actor.MODULE,
-            ],
-        )
-        try:
-            final = await tractor.to_actor.run(
-                partial(fib, n=10),
-                portal=portal,
-            )
-        finally:
-            await portal.cancel_actor()
-
 Pure RPC daemons: ``run_daemon()``
 ----------------------------------
 When a process's *only* job is to sit at the root of its own

docs/guide/spawning.rst

@@ -105,9 +105,9 @@ What's going on here?
 
 ``to_actor.run()``: quick one-shot parallelism
 ----------------------------------------------
-Without ``portal=``, :func:`tractor.to_actor.run` is the convenience
+:func:`tractor.to_actor.run` is the convenience wrapper: spawn
-wrapper: spawn an actor, run exactly one async function in it, block
+an actor, run exactly one async function in it, block on the
-on the result, then reap the process — the distributed sibling of
+result, then reap the process — the distributed sibling of
 ``trio.to_thread.run_sync()``.
 
 .. code:: python
@@ -126,10 +126,6 @@ A few details worth knowing:
   ``name='something_cuter'``.
 - the function's module is auto-added to the child's
   ``enable_modules`` allowlist.
-- targets cross IPC as ``module:name`` references, so portable calls
-  use module-global async functions or ``functools.partial`` objects
-  wrapping them. Nested functions, methods and callable objects do not
-  provide that stable address.
 - target arguments are positional; use ``functools.partial()``
   to bind target keyword arguments. Keywords passed directly to
   ``run()`` configure actor placement and spawning.
@@ -137,23 +133,18 @@ A few details worth knowing:
   child is *auto-cancelled* (reaped) right after — so remote
   errors raise directly in your calling task (causality_ is
   paramount!).
-- "placement" composes: ``an=`` spawns a call-owned child from an
+- "placement" composes: ``an=`` spawns from a caller-managed
-  existing actor nursery, while passing neither opens a private
+  actor-nursery, ``portal=`` reuses an already-running actor
-  call-scoped nursery. ``portal=`` instead reuses an existing actor:
+  (no spawn/reap), and passing neither opens a private
-  the call scopes only its linked remote task, neither spawns nor
+  call-scoped nursery (booting the runtime if needed).
-  reaps the actor, and leaves its lifetime with the portal's owner.
-  That actor must expose both the target module and
-  ``tractor.to_actor.MODULE``.
 
 .. note::
 
    :func:`tractor.to_actor.run` is a convenience, **not** the core
-   model. For actor-owning placements it combines
+   model — it's built *entirely* on
-   :meth:`~tractor.ActorNursery.start_actor`, a linked
+   :meth:`~tractor.ActorNursery.start_actor` plus a linked
-   :meth:`~tractor.Portal.open_context` call, and per-child
+   :meth:`~tractor.Portal.open_context` call and per-child
-   cancellation/reaping. With ``portal=`` it uses only the linked
+   cancellation/reaping. Teach your fingers to use it for quick
-   context call and leaves the existing actor's lifetime untouched.
-   Teach your fingers to use it for quick
    fire-and-collect parallelism — think a per-function trio-parallel_
    style one-shot — and reach for
    :meth:`~tractor.ActorNursery.start_actor` plus
@@ -162,25 +153,25 @@ A few details worth knowing:
 
 Actor lifetimes and teardown order
 ----------------------------------
-There are two actor-lifetime flavors:
+So we have two lifetime flavors:
 
-- **call-owned one-shot** (``to_actor.run()`` without ``portal=``):
+- **one-shot** (``to_actor.run()``): lives exactly as long as
-  spawned for one task, then cancelled and joined before ``run()``
+  its single task; reaped the moment its result (or error)
-  returns its result or raises its error.
+  arrives back in the (blocking) call.
-- **caller-owned daemon** (:meth:`~tractor.ActorNursery.start_actor`),
+- **daemon** (:meth:`~tractor.ActorNursery.start_actor`): lives
-  including an actor later reused through
+  until *someone* cancels it — an explicit
-  ``to_actor.run(..., portal=portal)``: lives until *someone*
-  cancels it via an explicit
   :meth:`~tractor.Portal.cancel_actor`, a bulk
   :meth:`~tractor.ActorNursery.cancel`, or the one-cancels-all
   strategy kicking in on error.
 
 On a clean exit of the nursery block the teardown order is:
 
-1. call-owned actors do not survive their own ``to_actor.run()``
+1. one-shot actors never make it to nursery exit: each is
-   calls; each is reaped before its call returns.
+   reaped inside its own ``to_actor.run()`` call, any error
-2. the nursery waits on caller-owned daemon actors
+   raising immediately in the calling task so your code
-   **indefinitely**. If you spawned one, you own its lifetime.
+   (acting as supervisor) gets first crack at handling it.
+2. the nursery then waits on daemon actors — **indefinitely**.
+   If you spawned a daemon, you own its lifetime.
 
 When a child *is* cancelled, teardown is graceful-first per SC
 discipline: the runtime sends an IPC cancel request and gives

docs/start/quickstart.rst

@@ -43,16 +43,15 @@ Run it::
 What's going on here?
 
 - ``trio.run(main)`` starts the **root actor**; the ``tractor``
-  runtime boots *implicitly* inside this ``tractor.to_actor.run()``
+  runtime boots *implicitly* inside ``tractor.to_actor.run()``
-  call because neither ``an=`` nor ``portal=`` was supplied. No
+  whenever it isn't already up. No special entrypoint, no
-  special entrypoint, no framework takeover - it's just a ``trio``
+  framework takeover - it's just a ``trio`` app,
-  app,
 - inside ``main()`` a *subactor* is spawned via
   ``tractor.to_actor.run()`` and told to run exactly one
   function: ``cellar_door()``,
 - the subactor, *some_linguist*, boots a fresh ``trio.run()`` in
-  a **new process** and executes ``cellar_door()`` as its linked
+  a **new process** and executes ``cellar_door()`` as its *main
-  one-shot task (note the child proving it is *not* the root with
+  task* (note the child proving it is *not* the root with
   ``tractor.is_root_process()``), then ships the return value
   back over IPC,
 - the call *blocks* until that final result arrives, then
@@ -68,10 +67,10 @@ What's going on here?
 
 .. note::
 
-   Without ``portal=``, ``to_actor.run()`` (parlance of
+   ``to_actor.run()`` (parlance of ``trio.to_thread`` and
-   ``trio.to_thread`` and friends) is the *convenience* wrapper:
+   friends) is the *convenience* wrapper: one-shot
-   one-shot spawn-run-reap semantics for when a subactor's entire
+   spawn-run-reap semantics for when a subactor's entire job is
-   job is a single function call. The core primitives are
+   a single function call. The core primitives are
    :meth:`~tractor.ActorNursery.start_actor` (next up) — which
    hands you a ``Portal``, your handle for invoking tasks in the
    new process's (separate!) memory domain — paired with
@@ -80,10 +79,10 @@ What's going on here?
 
 Daemon actors and RPC
 ---------------------
-A subactor spawned by ``to_actor.run()`` terminates after its lone
+A ``to_actor.run()`` one-shot subactor terminates when its lone
-task returns. But often you want long-lived *daemon* actors instead:
+task returns. But often you want long-lived *daemon* actors
-spawned once, then serving (allowlisted) RPC requests until told
+instead: spawned once, then serving (allowlisted) RPC requests
-otherwise. That's ``start_actor()``:
+until told otherwise. That's ``start_actor()``:
 
 .. literalinclude:: ../../examples/actor_spawning_and_causality_with_daemon.py
    :caption: examples/actor_spawning_and_causality_with_daemon.py
@@ -91,17 +90,14 @@ otherwise. That's ``start_actor()``:
 
 Two lifetime rules to internalize:
 
-- a subactor spawned and owned by ``to_actor.run()`` is cancelled
+- a ``to_actor.run()`` one-shot actor lives exactly as long as
-  and reaped before the call returns its result or raises its error,
+  its lone task; the call blocks until that function (and thus
+  the process) completes,
 - a ``start_actor()`` actor *lives forever* - an RPC daemon the
   nursery will happily wait on **indefinitely** - until some
   task explicitly cancels it via ``Portal.cancel_actor()`` (as
   above), or its parent nursery is cancelled wholesale.
 
-Passing ``portal=`` is different: the call owns only the linked
-remote task. It neither spawns nor reaps the existing actor; the
-portal's owner must end that actor's lifetime.
-
 .. tip::
 
    Want your *entire program* to just be a long-lived RPC

nooz/477.feature.rst

@@ -1,3 +0,0 @@
-Add ``tractor.to_actor.run()`` for Trio-style one-shot async calls in
-new or existing actors, with caller-scoped result/error propagation,
-linked cancellation, and deterministic reaping of call-owned children.

tests/ipc/test_each_tpt.py

@@ -15,10 +15,7 @@ from unittest.mock import Mock
 
 import pytest
 import trio
-from trio.testing import (
+from trio.testing import wait_all_tasks_blocked
-    MockClock,
-    wait_all_tasks_blocked,
-)
 import tractor
 from tractor import Actor
 from tractor.discovery import _addr
@@ -137,65 +134,6 @@ def test_cancelled_transport_send_completes_frame():
     trio.run(main)
 
 
-def test_transport_send_deadline_closes_partial_frame():
-    '''
-    Bound one shielded frame without exposing a corrupt stream.
-
-    Ordinary cancellation cannot interrupt complete-frame publication.
-    Actor-wide cancellation instead passes its absolute deadline into
-    this operation. The fake stream writes a partial header and stalls;
-    when the send's own deadline fires, the transport must close the
-    stream before releasing its shared send lock and report the channel
-    unusable.
-
-    '''
-    class StalledStream:
-        def __init__(self) -> None:
-            self.closed = False
-            self.wire = bytearray()
-
-        async def send_all(
-            self,
-            data: bytes,
-        ) -> None:
-            self.wire.extend(data[:2])
-            await trio.sleep_forever()
-
-        async def aclose(self) -> None:
-            self.closed = True
-
-    async def main() -> None:
-        stream = StalledStream()
-        transport = object.__new__(MsgpackTransport)
-        transport.stream = stream
-        transport._send_lock = trio.StrictFIFOLock()
-        msg = tractor.msg.Start(
-            ns=__name__,
-            func='add_one',
-            kwargs={'n': 1},
-            uid=('root', 'test'),
-            cid='deadline-send',
-        )
-
-        with pytest.raises(
-            tractor.TransportClosed,
-            match='frame publication exceeded',
-        ):
-            await transport.send(
-                msg,
-                send_deadline=1,
-            )
-
-        assert stream.closed
-        assert len(stream.wire) == 2
-        assert not transport._send_lock.locked()
-
-    trio.run(
-        main,
-        clock=MockClock(autojump_threshold=0),
-    )
-
-
 def test_cancelled_transport_send_preserves_cancellation():
     '''
     Prefer sender cancellation when teardown closes the stream.

tests/test_to_actor.py

@@ -8,21 +8,17 @@ https://github.com/goodboy/tractor/issues/477
 '''
 from functools import partial
 from pathlib import Path
-from types import SimpleNamespace
 
 import pytest
 import trio
-from trio.testing import MockClock
 import tractor
 from tractor import (
     RemoteActorError,
     to_actor,
 )
 from tractor._testing import tractor_test
-from tractor._exceptions import ActorTooSlowError
 from tractor.msg import ptr as msgptr
 from tractor.msg.ptr import NamespacePath
-from tractor.spawn import _mp as mp_spawn
 from tractor.to_actor import _api as to_actor_api
 
 
@@ -258,186 +254,6 @@ async def test_cancel_ack_failure_hard_reaps_child(
         assert not an._children
 
 
-def test_cancel_actor_timeout_closes_blocked_send():
-    '''
-    Thread one absolute cancel deadline into shielded frame publication.
-
-    The cancel RPC's outer timeout cannot penetrate a complete-frame
-    shield. The fake private RPC applies the forwarded send deadline to
-    its own shielded wait, then checkpoints into the outer scope. A
-    bounded `ActorTooSlowError` and the recorded absolute deadline prove
-    publication and acknowledgement share one timeout budget.
-
-    '''
-    class ConnectedChannel:
-        def __init__(self) -> None:
-            self._cancel_called = False
-            self.aid = tractor.msg.Aid(
-                name='blocked_peer',
-                uuid='test',
-            )
-
-        def connected(self) -> bool:
-            return True
-
-    async def main() -> None:
-        channel = ConnectedChannel()
-        portal = object.__new__(tractor.Portal)
-        portal._chan = channel
-        deadlines: list[float] = []
-
-        async def blocked_cancel(
-            namespace: str,
-            function: str,
-            kwargs: dict[str, object],
-            cancel_on_startup: bool,
-            send_deadline: float,
-        ) -> None:
-            assert (namespace, function) == ('self', 'cancel')
-            assert kwargs == {}
-            assert not cancel_on_startup
-            deadlines.append(send_deadline)
-            with trio.CancelScope(
-                deadline=send_deadline,
-                shield=True,
-            ):
-                await trio.sleep_forever()
-            await trio.lowlevel.checkpoint_if_cancelled()
-
-        portal._run_from_ns = blocked_cancel
-        with pytest.raises(ActorTooSlowError):
-            await portal.cancel_actor(
-                timeout=1,
-                raise_on_timeout=True,
-            )
-
-        assert deadlines == [1.]
-
-    trio.run(
-        main,
-        clock=MockClock(autojump_threshold=0),
-    )
-
-
-def _mock_actor_nursery() -> tractor.ActorNursery:
-    an = object.__new__(tractor.ActorNursery)
-    an._children = {}
-    an._join_procs = trio.Event()
-    an._child_reap_requests = {}
-    an._child_reaped = {}
-    an._at_least_one_child_in_debug = False
-    an._cancel_called = False
-    return an
-
-
-def test_late_child_registration_observes_cancel():
-    '''
-    Make registration atomically observe nursery cancellation.
-
-    `ActorNursery.cancel()` previously snapshotted `_children` before
-    its next checkpoint. A process monitor registering after that
-    snapshot received a reap request but no runtime cancellation, then
-    waited forever for natural exit. Publishing the child and its reap
-    events together returns cancellation ownership to the late monitor.
-
-    '''
-    an = _mock_actor_nursery()
-    an._cancel_called = True
-    aid = tractor.msg.Aid(
-        name='late_child',
-        uuid='test',
-    )
-    subactor = SimpleNamespace(aid=aid)
-    proc = object()
-
-    (
-        reap_request,
-        reaped,
-        cancel_during_registration,
-    ) = an._register_child(
-        subactor,
-        proc,
-        None,
-    )
-
-    assert cancel_during_registration
-    assert an._children[aid.uid] == (
-        subactor,
-        proc,
-        None,
-    )
-    assert an._child_reap_requests[aid.uid] is reap_request
-    assert an._child_reaped[aid.uid] is reaped
-
-
-def test_mp_late_registration_never_starts_process(
-    monkeypatch: pytest.MonkeyPatch,
-):
-    '''
-    Refuse to start an MP child already owned by nursery cancellation.
-
-    A concurrent `ActorNursery.cancel()` can publish cancellation after
-    `start_actor()` checks its flag but before the MP backend registers
-    its process. The fake registration reports that exact schedule.
-    Proving `FakeProcess.start()` is never called prevents a child from
-    starting after it was omitted from the cancellation snapshot.
-
-    '''
-    class FakeProcess:
-        started: bool = False
-
-        def start(self) -> None:
-            self.started = True
-
-    process = FakeProcess()
-
-    class FakeContext:
-        def get_start_method(self) -> str:
-            return 'spawn'
-
-        def Process(self, **kwargs: object) -> FakeProcess:
-            assert kwargs
-            return process
-
-    nursery = SimpleNamespace(
-        _register_child=lambda *args: (
-            trio.Event(),
-            trio.Event(),
-            True,
-        ),
-    )
-    subactor = SimpleNamespace(
-        aid=tractor.msg.Aid(
-            name='late_mp_child',
-            uuid='test',
-        ),
-    )
-    monkeypatch.setattr(
-        mp_spawn._spawn,
-        '_ctx',
-        FakeContext(),
-    )
-
-    with pytest.raises(
-        RuntimeError,
-        match='nursery began cancelling',
-    ):
-        trio.run(
-            partial(
-                mp_spawn.mp_proc,
-                name='late_mp_child',
-                actor_nursery=nursery,
-                subactor=subactor,
-                errors={},
-                bind_addrs=[],
-                parent_addr=SimpleNamespace(),
-                _runtime_vars={},
-            )
-        )
-
-    assert not process.started
-
-
 def test_late_child_reap_registration_is_released():
     '''
     Preserve a nursery-wide reap request across child startup.

tractor/ipc/_chan.py

@@ -310,7 +310,6 @@ class Channel:
         payload: Any,
 
         hide_tb: bool = False,
-        send_deadline: float = float('inf'),
 
     ) -> None:
         '''
@@ -321,9 +320,6 @@ class Channel:
         expected-graceful cases, normally ephemercal
         (re/dis)connects.
 
-        `send_deadline` is an absolute Trio clock deadline forwarded
-        only to transports that support bounded frame publication.
-
         '''
         __tracebackhide__: bool = hide_tb
         try:
@@ -334,17 +330,10 @@ class Channel:
                     f'{pformat(payload)}\n'
                 )
             # assert self._transport  # but why typing?
-            if send_deadline == float('inf'):
             await self._transport.send(
                 payload,
                 hide_tb=hide_tb,
             )
-            else:
-                await self._transport.send(
-                    payload,
-                    hide_tb=hide_tb,
-                    send_deadline=send_deadline,
-                )
         except (
             BaseException,
             MsgTypeError,

tractor/ipc/_transport.py

@@ -439,7 +439,6 @@ class MsgpackTransport(MsgTransport):
 
         strict_types: bool = True,
         hide_tb: bool = True,
-        send_deadline: float = float('inf'),
 
     ) -> None:
         '''
@@ -448,10 +447,6 @@ class MsgpackTransport(MsgTransport):
         If `strict_types == True` then a `MsgTypeError` will be raised on any
         invalid msg type
 
-        `send_deadline` bounds publication of this complete frame. A
-        timeout destroys the stream because a partial prefix may have
-        reached the wire.
-
         '''
         __tracebackhide__: bool = hide_tb
 
@@ -518,26 +513,12 @@ class MsgpackTransport(MsgTransport):
                 # the frame is complete, the explicit checkpoint
                 # immediately delivers any pending cancellation.
                 #
-                # Ordinary sends may delay cancellation while a peer is
+                # This can delay cancellation while a peer is not
-                # not reading. Actor-wide cancel requests pass their own
+                # reading; peer/channel teardown must close the stream
-                # deadline so this operation can close a stalled stream.
+                # to unblock a permanently stalled socket write.
-                with trio.CancelScope(
+                with trio.CancelScope(shield=True):
-                    deadline=send_deadline,
-                    shield=True,
-                ) as send_cs:
                     await self.stream.send_all(size + bytes_data)
 
-                if send_cs.cancelled_caught:
-                    # This frame may be partial. Destroy the stream
-                    # before releasing `_send_lock` so no later sender
-                    # can append bytes to a corrupted frame.
-                    await trio.aclose_forcefully(self.stream)
-                    await trio.lowlevel.checkpoint_if_cancelled()
-                    raise TransportClosed(
-                        'IPC frame publication exceeded its '
-                        f'deadline of {send_deadline!r}'
-                    )
-
                 await trio.lowlevel.checkpoint_if_cancelled()
                 return None
 

tractor/runtime/_portal.py

@@ -319,53 +319,39 @@ class Portal:
             or
             self.cancel_timeout
         )
-        cancel_deadline: float = (
-            trio.current_time()
-            +
-            cancel_timeout
-        )
-        # NOTE: Actor-runtime cancellation currently rides the normal
-        # RPC envelope:
-        #
-        # `Start(self.cancel)` -> `StartAck` -> `CancelAck`.
-        #
-        # `Actor.start_remote_task()` consumes the `StartAck`, then
-        # `._run_from_ns()` returns only after `PldRx.recv_pld()`
-        # decodes the final `CancelAck`. Thus this flag means that ack
-        # reached this portal after the peer's `Actor.cancel()` routine
-        # completed; it does not prove the peer OS process has exited.
-        # A dedicated `Cancel` request msg can eventually replace the
-        # internal `Start` RPC envelope and its extra `StartAck`.
-        cancel_ack_received: bool = False
         try:
-            with trio.move_on_at(cancel_deadline) as cs:
+            # send cancel cmd - might not get response
+            # XXX: sure would be nice to make this work with
+            # a proper shield
+            with trio.move_on_after(cancel_timeout) as cs:
                 cs.shield: bool = True
-                await self._run_from_ns(
+                await self.run_from_ns(
                     'self',
                     'cancel',
-                    kwargs={},
-                    cancel_on_startup=False,
-                    send_deadline=cancel_deadline,
                 )
-                cancel_ack_received = True
+                return True
 
-            # Preserve shielded actor teardown, then immediately
+            # `move_on_after` fired — peer didn't ack within
-            # redeliver any cancellation pending from an outer scope.
-            await trio.lowlevel.checkpoint_if_cancelled()
-
-            # `move_on_at` fired — peer didn't ack within
             # bounded window. Behaviour depends on
             # `raise_on_timeout`:
-            if cs.cancelled_caught:
+            if (
-                if raise_on_timeout:
+                cs.cancelled_caught
+                and
+                raise_on_timeout
+            ):
                 raise ActorTooSlowError(
                     f'Peer {peer_id} did not ack its '
                     f'`Actor.cancel()` RPC within bounded wait '
                     f'of {cancel_timeout!r}s'
                 )
 
-                # Legacy fire-and-forget callers decide whether to
+            # legacy fire-and-forget path: log + return False so
-                # escalate the missed acknowledgement themselves.
+            # the caller can decide whether to escalate.
+            #
+            # NOTE, we also land here in the (unexpected) case where
+            # the shielded `move_on_after` block exits WITHOUT
+            # `return True` and WITHOUT the deadline firing — prefer
+            # a soft `False` over an `assert`-crash mid-teardown.
             log.debug(
                 f'May have failed to cancel peer?\n'
                 f'\n'
@@ -373,8 +359,6 @@ class Portal:
             )
             return False
 
-            return cancel_ack_received
-
         except TransportClosed as tpt_err:
             ipc_borked_report: str = (
                 f'IPC for actor already closed/broken?\n\n'
@@ -395,24 +379,16 @@ class Portal:
 
             return False
 
-    # TODO: Replace actor-runtime cancellation's internal
-    # `Start -> StartAck -> CancelAck` RPC with a dedicated
-    # `Cancel -> CancelAck` transaction:
-    # https://github.com/goodboy/tractor/issues/506
     async def _run_from_ns(
         self,
         namespace_path: str,
         function_name: str,
         kwargs: dict[str, Any],
         cancel_on_startup: bool = True,
-        send_deadline: float = float('inf'),
     ) -> Any:
         '''
         Run a namespace target with local startup policy controls.
 
-        `send_deadline` bounds only publication of the `Start` frame;
-        the caller owns any larger RPC/acknowledgement deadline.
-
         '''
         nsf = NamespacePath(
             f'{namespace_path}:{function_name}'
@@ -423,7 +399,6 @@ class Portal:
             kwargs=kwargs,
             portal=self,
             cancel_on_startup=cancel_on_startup,
-            send_deadline=send_deadline,
         )
         try:
             return await ctx._pld_rx.recv_pld(

tractor/runtime/_runtime.py

@@ -793,11 +793,6 @@ class Actor:
         ack_timeout: float = float('inf'),
         cancel_on_startup: bool = True,
 
-        # Optional absolute deadline for publishing this exact `Start`
-        # frame. Used by actor-wide cancel RPCs whose outer timeout
-        # cannot penetrate complete-frame transport shielding.
-        send_deadline: float = float('inf'),
-
     ) -> Context:
         '''
         Send a `'cmd'` msg to a remote actor, which requests the
@@ -850,13 +845,7 @@ class Actor:
         )
         start_published: bool = False
         try:
-            if send_deadline == float('inf'):
             await chan.send(msg)
-            else:
-                await chan.send(
-                    msg,
-                    send_deadline=send_deadline,
-                )
             start_published = True
 
             # NOTE wait on first `StartAck` response msg and validate;

tractor/runtime/_supervise.py

@@ -327,29 +327,6 @@ class ActorNursery:
             reap_request.set()
         return reap_request, reaped
 
-    def _register_child(
-        self,
-        subactor: Actor,
-        proc: 'ProcessType',
-        portal: Portal|None,
-    ) -> tuple[trio.Event, trio.Event, bool]:
-        '''
-        Atomically publish one child and its reap coordination.
-
-        '''
-        uid: tuple[str, str] = subactor.aid.uid
-        self._children[uid] = (
-            subactor,
-            proc,
-            portal,
-        )
-        reap_request, reaped = self._register_child_reap(uid)
-        return (
-            reap_request,
-            reaped,
-            self._cancel_called,
-        )
-
     def _request_reap_all(self) -> None:
         '''
         Release every child monitor into its process-join phase.
@@ -442,12 +419,6 @@ class ActorNursery:
 
         '''
         __runtimeframe__: int = 1  # noqa
-        if self._cancel_called:
-            raise RuntimeError(
-                'Cannot start an actor in a cancelling '
-                '`ActorNursery`'
-            )
-
         loglevel: str = (
             loglevel
             or self._actor.loglevel

tractor/spawn/_mp.py

@@ -138,22 +138,12 @@ async def mp_proc(
         # daemon=True,
         name=name,
     )
-    # `multiprocessing` only (since no async interface): publish the
+
-    # process and its reap coordination before start so cancellation
+    # `multiprocessing` only (since no async interface):
-    # can own every subsequently started child.
+    # register the process before start in case we get a cancel
-    (
+    # request before the actor has fully spawned - then we can wait
-        reap_request,
+    # for it to fully come up before sending a cancel request
-        _,
+    actor_nursery._children[subactor.aid.uid] = (subactor, proc, None)
-        cancel_during_registration,
-    ) = actor_nursery._register_child(
-        subactor,
-        proc,
-        None,
-    )
-    if cancel_during_registration:
-        raise RuntimeError(
-            'Actor registered after its nursery began cancelling'
-        )
 
     proc.start()
     if not proc.is_alive():
@@ -180,6 +170,9 @@ async def mp_proc(
         # any process we may have started.
 
         portal = Portal(chan)
+        reap_request, _ = actor_nursery._register_child_reap(
+            subactor.aid.uid,
+        )
         actor_nursery._children[subactor.aid.uid] = (subactor, proc, portal)
 
         # unblock parent task

tractor/spawn/_trio.py

@@ -39,6 +39,7 @@ from tractor.runtime._state import (
     current_actor,
     is_root_process,
     debug_mode,
+    get_runtime_vars,
 )
 from tractor.log import get_logger
 from tractor.discovery._addr import UnwrappedAddress
@@ -130,23 +131,6 @@ async def trio_proc(
                 f' |_{proc}\n'
             )
 
-            (
-                reap_request,
-                _,
-                cancel_during_registration,
-            ) = actor_nursery._register_child(
-                subactor,
-                proc,
-                None,
-            )
-            if cancel_during_registration:
-                cancelled_during_spawn = True
-                proc.kill()
-                raise RuntimeError(
-                    'Actor registered after its nursery began '
-                    'cancelling'
-                )
-
             # wait for actor to spawn and connect back to us
             # channel should have handshake completed by the
             # local actor by the time we get a ref to it
@@ -177,6 +161,9 @@ async def trio_proc(
         assert proc
 
         portal = Portal(chan)
+        reap_request, _ = actor_nursery._register_child_reap(
+            subactor.aid.uid,
+        )
         actor_nursery._children[subactor.aid.uid] = (
             subactor,
             proc,