Unwind process opening and shield hard reap

immediate_remote_cancels
Tyler Goodlet 2021-10-12 23:59:39 -04:00
parent bb9d9c74b1
commit 46ff558556
1 changed files with 72 additions and 91 deletions

View File

@ -174,48 +174,6 @@ async def do_hard_kill(
proc.kill()
@asynccontextmanager
async def spawn_subactor(
subactor: 'Actor',
parent_addr: Tuple[str, int],
):
spawn_cmd = [
sys.executable,
"-m",
# Hardcode this (instead of using ``_child.__name__`` to avoid a
# double import warning: https://stackoverflow.com/a/45070583
"tractor._child",
# We provide the child's unique identifier on this exec/spawn
# line for debugging purposes when viewing the process tree from
# the OS; it otherwise can be passed via the parent channel if
# we prefer in the future (for privacy).
"--uid",
str(subactor.uid),
# Address the child must connect to on startup
"--parent_addr",
str(parent_addr)
]
if subactor.loglevel:
spawn_cmd += [
"--loglevel",
subactor.loglevel
]
proc = await trio.open_process(spawn_cmd)
try:
yield proc
finally:
log.runtime(f"Attempting to kill {proc}")
# XXX: do this **after** cancellation/tearfown
# to avoid killing the process too early
# since trio does this internally on ``__aexit__()``
await do_hard_kill(proc)
async def new_proc(
name: str,
actor_nursery: 'ActorNursery', # type: ignore # noqa
@ -228,8 +186,10 @@ async def new_proc(
*,
task_status: TaskStatus[Portal] = trio.TASK_STATUS_IGNORED
) -> None:
"""Create a new ``multiprocessing.Process`` using the
"""
Create a new ``multiprocessing.Process`` using the
spawn method as configured using ``try_set_start_method()``.
"""
cancel_scope = None
@ -237,43 +197,66 @@ async def new_proc(
subactor._spawn_method = _spawn_method
if _spawn_method == 'trio':
async with trio.open_nursery() as nursery:
async with spawn_subactor(
subactor,
parent_addr,
) as proc:
log.runtime(f"Started {proc}")
# 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
event, chan = await actor_nursery._actor.wait_for_peer(
subactor.uid)
portal = Portal(chan)
actor_nursery._children[subactor.uid] = (
subactor, proc, portal)
spawn_cmd = [
sys.executable,
"-m",
# Hardcode this (instead of using ``_child.__name__`` to avoid a
# double import warning: https://stackoverflow.com/a/45070583
"tractor._child",
# We provide the child's unique identifier on this exec/spawn
# line for debugging purposes when viewing the process tree from
# the OS; it otherwise can be passed via the parent channel if
# we prefer in the future (for privacy).
"--uid",
str(subactor.uid),
# Address the child must connect to on startup
"--parent_addr",
str(parent_addr)
]
# send additional init params
await chan.send({
"_parent_main_data": subactor._parent_main_data,
"enable_modules": subactor.enable_modules,
"_arb_addr": subactor._arb_addr,
"bind_host": bind_addr[0],
"bind_port": bind_addr[1],
"_runtime_vars": _runtime_vars,
})
if subactor.loglevel:
spawn_cmd += [
"--loglevel",
subactor.loglevel
]
# track subactor in current nursery
curr_actor = current_actor()
curr_actor._actoruid2nursery[subactor.uid] = actor_nursery
try:
proc = await trio.open_process(spawn_cmd)
# resume caller at next checkpoint now that child is up
task_status.started(portal)
log.runtime(f"Started {proc}")
# wait for ActorNursery.wait() to be called
with trio.CancelScope(shield=True):
await actor_nursery._join_procs.wait()
# 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
event, chan = await actor_nursery._actor.wait_for_peer(
subactor.uid)
portal = Portal(chan)
actor_nursery._children[subactor.uid] = (
subactor, proc, portal)
# send additional init params
await chan.send({
"_parent_main_data": subactor._parent_main_data,
"enable_modules": subactor.enable_modules,
"_arb_addr": subactor._arb_addr,
"bind_host": bind_addr[0],
"bind_port": bind_addr[1],
"_runtime_vars": _runtime_vars,
})
# track subactor in current nursery
curr_actor = current_actor()
curr_actor._actoruid2nursery[subactor.uid] = actor_nursery
# resume caller at next checkpoint now that child is up
task_status.started(portal)
# wait for ActorNursery.wait() to be called
with trio.CancelScope(shield=True):
await actor_nursery._join_procs.wait()
async with trio.open_nursery() as nursery:
if portal in actor_nursery._cancel_after_result_on_exit:
cancel_scope = await nursery.start(
cancel_on_completion,
@ -285,25 +268,10 @@ async def new_proc(
# Wait for proc termination but **dont' yet** call
# ``trio.Process.__aexit__()`` (it tears down stdio
# which will kill any waiting remote pdb trace).
# TODO: No idea how we can enforce zombie
# reaping more stringently without the shield
# we used to have below...
# with trio.CancelScope(shield=True):
# async with proc:
# Always "hard" join sub procs since no actor zombies
# are allowed!
# this is a "light" (cancellable) join, the hard join is
# in the enclosing scope (see above).
# This is a "soft" (cancellable) join/reap.
await proc.wait()
log.debug(f"Joined {proc}")
# pop child entry to indicate we no longer managing this subactor
subactor, proc, portal = actor_nursery._children.pop(subactor.uid)
finally:
# cancel result waiter that may have been spawned in
# tandem if not done already
if cancel_scope:
@ -311,6 +279,19 @@ async def new_proc(
"Cancelling existing result waiter task for "
f"{subactor.uid}")
cancel_scope.cancel()
log.runtime(f"Attempting to kill {proc}")
# The "hard" reap since no actor zombies are allowed!
# XXX: do this **after** cancellation/tearfown to avoid
# killing the process too early.
with trio.CancelScope(shield=True):
await do_hard_kill(proc)
log.debug(f"Joined {proc}")
# pop child entry to indicate we no longer managing this subactor
subactor, proc, portal = actor_nursery._children.pop(subactor.uid)
else:
# `multiprocessing`
# async with trio.open_nursery() as nursery: