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Author SHA1 Message Date
Tyler Goodlet a89799b682 Handle broken mem chan on `Actor._push_result()`
When backpressure is used and a feeder mem chan breaks during msg
delivery (usually because the IPC allocating task already terminated)
instead of raising we simply warn as we do for the non-backpressure
case.

Also, add a proper `Actor.is_arbiter` test inside `._invoke()` to avoid
doing an arbiter-registry lookup if the current actor **is** the
registrar.
2022-12-12 15:04:40 -05:00
Tyler Goodlet 45a9aaf6e9 Always set the `parent_exit: trio.Event` on exit 2022-12-12 15:04:40 -05:00
Tyler Goodlet b624ebba21 Add logging and teardown prints to full-fledged-streaming example 2022-12-12 15:04:40 -05:00
Tyler Goodlet e12def51a8 Always print any std streams to console in docs examples tests 2022-12-12 15:04:40 -05:00
Tyler Goodlet 64819b2acb Skip debugger tests on OS X for now 2022-12-12 15:04:40 -05:00
Tyler Goodlet a5e3cf4ecf Add macos run using only the `trio` spawner 2022-12-12 15:04:40 -05:00
Tyler Goodlet 7c42d2510c Add back `pytest` full trace flag to debug CI hangs 2022-12-12 15:04:40 -05:00
Tyler Goodlet 9c336ec064 Add `numpy` for testing optional integrated shm API layer 2022-12-12 15:04:11 -05:00
Tyler Goodlet 6453195e97 Pass `str` dtype for `use_str` case 2022-12-12 15:04:11 -05:00
Tyler Goodlet 54322f2bae Allocate size-specced "empty" sequence from default values by type 2022-12-12 15:04:11 -05:00
Tyler Goodlet 1be3f4115d Mod define `_USE_POSIX`, add a of of todos 2022-12-12 15:04:11 -05:00
Tyler Goodlet 3bdd04ef4a Parametrize rw test with variable frame sizes
Demonstrates fixed size frame-oriented reads by the child where the
parent only transmits a "read" stream msg on "frame fill events" such
that the child incrementally reads the shm list data (much like in
a real-time-buffered streaming system).
2022-12-12 15:04:11 -05:00
Tyler Goodlet 2ac19b2e96 Add `ShmList` slice support in `.__getitem__()` 2022-12-12 15:04:11 -05:00
Tyler Goodlet 60f8f110e8 Rename token type to `NDToken` in the style of `nptyping` 2022-12-12 15:04:11 -05:00
Tyler Goodlet 6d4d428205 Fix uid2nursery lookup table type annot 2022-12-12 15:04:11 -05:00
Tyler Goodlet ecea1e1658 Don't require runtime (for now), type annot fixing 2022-12-12 15:04:11 -05:00
Tyler Goodlet 971ac50756 Add repetitive attach to existing segment test 2022-12-12 15:04:11 -05:00
Tyler Goodlet c01c22769b Add initial readers-writer shm list tests 2022-12-12 15:04:11 -05:00
Tyler Goodlet 0e4b37d122 Add `ShmList` wrapping the stdlib's `ShareableList`
First attempt at getting `multiprocessing.shared_memory.ShareableList`
working; we wrap the stdlib type with a readonly attr and a `.key` for
cross-actor lookup. Also, rename all `numpy` specific routines to have
a `ndarray` suffix in the func names.
2022-12-12 15:04:11 -05:00
Tyler Goodlet 901353c213 Initial module import from `piker.data._sharemem`
More or less a verbatim copy-paste minus some edgy variable naming and
internal `piker` module imports. There is a bunch of OHLC related
defaults that need to be dropped and we need to adjust to an optional
dependence on `numpy` by supporting shared lists as per the mp docs.
2022-12-12 15:04:11 -05:00
9 changed files with 1093 additions and 39 deletions

View File

@ -67,7 +67,6 @@ jobs:
]
steps:
- name: Checkout
uses: actions/checkout@v2
@ -85,6 +84,40 @@ jobs:
- name: Run tests
run: pytest tests/ --spawn-backend=${{ matrix.spawn_backend }} -rsx
testing-macos:
name: '${{ matrix.os }} Python ${{ matrix.python }} - ${{ matrix.spawn_backend }}'
timeout-minutes: 10
runs-on: ${{ matrix.os }}
strategy:
fail-fast: false
matrix:
os: [macos-latest]
python: ['3.10']
spawn_backend: [
'trio',
]
steps:
- name: Checkout
uses: actions/checkout@v2
- name: Setup python
uses: actions/setup-python@v2
with:
python-version: '${{ matrix.python }}'
- name: Install dependencies
run: pip install -U . -r requirements-test.txt -r requirements-docs.txt --upgrade-strategy eager
- name: List dependencies
run: pip list
- name: Run tests
run: pytest tests/ --spawn-backend=${{ matrix.spawn_backend }} -rsx
# We skip 3.10 on windows for now due to not having any collabs to
# debug the CI failures. Anyone wanting to hack and solve them is very
# welcome, but our primary user base is not using that OS.

View File

@ -12,9 +12,11 @@ async def stream_data(seed):
# this is the third actor; the aggregator
async def aggregate(seed):
"""Ensure that the two streams we receive match but only stream
'''
Ensure that the two streams we receive match but only stream
a single set of values to the parent.
"""
'''
async with tractor.open_nursery() as nursery:
portals = []
for i in range(1, 3):
@ -69,7 +71,8 @@ async def aggregate(seed):
async def main():
# a nursery which spawns "actors"
async with tractor.open_nursery(
arbiter_addr=('127.0.0.1', 1616)
arbiter_addr=('127.0.0.1', 1616),
loglevel='cancel',
) as nursery:
seed = int(1e3)
@ -92,6 +95,9 @@ async def main():
async for value in stream:
result_stream.append(value)
print("ROOT STREAM CONSUMER COMPLETE")
print("ROOT CANCELLING AGGREGATOR CHILD")
await portal.cancel_actor()
print(f"STREAM TIME = {time.time() - start}")

View File

@ -6,3 +6,4 @@ mypy
trio_typing
pexpect
towncrier
numpy

View File

@ -36,9 +36,12 @@ from conftest import repodir, _ci_env
# - recurrent root errors
if platform.system() == 'Windows':
if osname := platform.system() in (
'Windows',
'Darwin',
):
pytest.skip(
'Debugger tests have no windows support (yet)',
'Debugger tests have no {osname} support (yet)',
allow_module_level=True,
)
@ -783,8 +786,6 @@ def test_multi_nested_subactors_error_through_nurseries(
child = spawn('multi_nested_subactors_error_up_through_nurseries')
timed_out_early: bool = False
for send_char in itertools.cycle(['c', 'q']):
try:
child.expect(r"\(Pdb\+\+\)")

View File

@ -93,14 +93,16 @@ def run_example_in_subproc(loglevel, testdir, arb_addr):
ids=lambda t: t[1],
)
def test_example(run_example_in_subproc, example_script):
"""Load and run scripts from this repo's ``examples/`` dir as a user
'''
Load and run scripts from this repo's ``examples/`` dir as a user
would copy and pasing them into their editor.
On windows a little more "finessing" is done to make
``multiprocessing`` play nice: we copy the ``__main__.py`` into the
test directory and invoke the script as a module with ``python -m
test_example``.
"""
'''
ex_file = os.path.join(*example_script)
if 'rpc_bidir_streaming' in ex_file and sys.version_info < (3, 9):
@ -110,13 +112,20 @@ def test_example(run_example_in_subproc, example_script):
code = ex.read()
with run_example_in_subproc(code) as proc:
proc.wait()
err, _ = proc.stderr.read(), proc.stdout.read()
# print(f'STDERR: {err}')
# print(f'STDOUT: {out}')
try:
proc.wait(timeout=5)
finally:
err = proc.stderr.read()
errmsg = err.decode()
out = proc.stdout.read()
outmsg = out.decode()
if out:
print(f'STDOUT: {out.decode()}')
# if we get some gnarly output let's aggregate and raise
if err:
print(f'STDERR:\n{errmsg}')
errmsg = err.decode()
errlines = errmsg.splitlines()
last_error = errlines[-1]

167
tests/test_shm.py 100644
View File

@ -0,0 +1,167 @@
"""
Shared mem primitives and APIs.
"""
import uuid
# import numpy
import pytest
import trio
import tractor
from tractor._shm import (
open_shm_list,
attach_shm_list,
)
@tractor.context
async def child_attach_shml_alot(
ctx: tractor.Context,
shm_key: str,
) -> None:
await ctx.started(shm_key)
# now try to attach a boatload of times in a loop..
for _ in range(1000):
shml = attach_shm_list(
key=shm_key,
readonly=False,
)
assert shml.shm.name == shm_key
await trio.sleep(0.001)
def test_child_attaches_alot():
async def main():
async with tractor.open_nursery() as an:
# allocate writeable list in parent
key = f'shml_{uuid.uuid4()}'
shml = open_shm_list(
key=key,
)
portal = await an.start_actor(
'shm_attacher',
enable_modules=[__name__],
)
async with (
portal.open_context(
child_attach_shml_alot,
shm_key=shml.key,
) as (ctx, start_val),
):
assert start_val == key
await ctx.result()
await portal.cancel_actor()
trio.run(main)
@tractor.context
async def child_read_shm_list(
ctx: tractor.Context,
shm_key: str,
use_str: bool,
frame_size: int,
) -> None:
# attach in child
shml = attach_shm_list(
key=shm_key,
# dtype=str if use_str else float,
)
await ctx.started(shml.key)
async with ctx.open_stream() as stream:
async for i in stream:
print(f'(child): reading shm list index: {i}')
if use_str:
expect = str(float(i))
else:
expect = float(i)
if frame_size == 1:
val = shml[i]
assert expect == val
print(f'(child): reading value: {val}')
else:
frame = shml[i - frame_size:i]
print(f'(child): reading frame: {frame}')
@pytest.mark.parametrize(
'use_str',
[False, True],
ids=lambda i: f'use_str_values={i}',
)
@pytest.mark.parametrize(
'frame_size',
[1, 2**6, 2**10],
ids=lambda i: f'frame_size={i}',
)
def test_parent_writer_child_reader(
use_str: bool,
frame_size: int,
):
async def main():
async with tractor.open_nursery(
# debug_mode=True,
) as an:
portal = await an.start_actor(
'shm_reader',
enable_modules=[__name__],
debug_mode=True,
)
# allocate writeable list in parent
key = 'shm_list'
seq_size = int(2 * 2 ** 10)
shml = open_shm_list(
key=key,
size=seq_size,
dtype=str if use_str else float,
readonly=False,
)
async with (
portal.open_context(
child_read_shm_list,
shm_key=key,
use_str=use_str,
frame_size=frame_size,
) as (ctx, sent),
ctx.open_stream() as stream,
):
assert sent == key
for i in range(seq_size):
val = float(i)
if use_str:
val = str(val)
# print(f'(parent): writing {val}')
shml[i] = val
# only on frame fills do we
# signal to the child that a frame's
# worth is ready.
if (i % frame_size) == 0:
print(f'(parent): signalling frame full on {val}')
await stream.send(i)
else:
print(f'(parent): signalling final frame on {val}')
await stream.send(i)
await portal.cancel_actor()
trio.run(main)

View File

@ -488,7 +488,10 @@ class Actor:
self._parent_chan: Optional[Channel] = None
self._forkserver_info: Optional[
tuple[Any, Any, Any, Any, Any]] = None
self._actoruid2nursery: dict[Optional[tuple[str, str]], 'ActorNursery'] = {} # type: ignore # noqa
self._actoruid2nursery: dict[
tuple[str, str],
ActorNursery | None,
] = {} # type: ignore # noqa
async def wait_for_peer(
self, uid: tuple[str, str]
@ -826,7 +829,12 @@ class Actor:
if ctx._backpressure:
log.warning(text)
try:
await send_chan.send(msg)
except trio.BrokenResourceError:
# XXX: local consumer has closed their side
# so cancel the far end streaming task
log.warning(f"{chan} is already closed")
else:
try:
raise StreamOverrun(text) from None
@ -1371,8 +1379,9 @@ async def async_main(
actor.lifetime_stack.close()
# Unregister actor from the arbiter
if registered_with_arbiter and (
actor._arb_addr is not None
if (
registered_with_arbiter
and not actor.is_arbiter
):
failed = False
with trio.move_on_after(0.5) as cs:

828
tractor/_shm.py 100644
View File

@ -0,0 +1,828 @@
# tractor: structured concurrent "actors".
# Copyright 2018-eternity Tyler Goodlet.
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
"""
SC friendly shared memory management geared at real-time
processing.
Support for ``numpy`` compatible array-buffers is provided but is
considered optional within the context of this runtime-library.
"""
from __future__ import annotations
from sys import byteorder
import time
from typing import Optional
from multiprocessing import shared_memory as shm
from multiprocessing.shared_memory import (
SharedMemory,
ShareableList,
)
from msgspec import Struct
import tractor
from .log import get_logger
_USE_POSIX = getattr(shm, '_USE_POSIX', False)
if _USE_POSIX:
from _posixshmem import shm_unlink
try:
import numpy as np
from numpy.lib import recfunctions as rfn
import nptyping
except ImportError:
pass
log = get_logger(__name__)
def disable_mantracker():
'''
Disable all ``multiprocessing``` "resource tracking" machinery since
it's an absolute multi-threaded mess of non-SC madness.
'''
from multiprocessing import resource_tracker as mantracker
# Tell the "resource tracker" thing to fuck off.
class ManTracker(mantracker.ResourceTracker):
def register(self, name, rtype):
pass
def unregister(self, name, rtype):
pass
def ensure_running(self):
pass
# "know your land and know your prey"
# https://www.dailymotion.com/video/x6ozzco
mantracker._resource_tracker = ManTracker()
mantracker.register = mantracker._resource_tracker.register
mantracker.ensure_running = mantracker._resource_tracker.ensure_running
mantracker.unregister = mantracker._resource_tracker.unregister
mantracker.getfd = mantracker._resource_tracker.getfd
disable_mantracker()
class SharedInt:
'''
Wrapper around a single entry shared memory array which
holds an ``int`` value used as an index counter.
'''
def __init__(
self,
shm: SharedMemory,
) -> None:
self._shm = shm
@property
def value(self) -> int:
return int.from_bytes(self._shm.buf, byteorder)
@value.setter
def value(self, value) -> None:
self._shm.buf[:] = value.to_bytes(self._shm.size, byteorder)
def destroy(self) -> None:
if _USE_POSIX:
# We manually unlink to bypass all the "resource tracker"
# nonsense meant for non-SC systems.
name = self._shm.name
try:
shm_unlink(name)
except FileNotFoundError:
# might be a teardown race here?
log.warning(f'Shm for {name} already unlinked?')
class NDToken(Struct, frozen=True):
'''
Internal represenation of a shared memory ``numpy`` array "token"
which can be used to key and load a system (OS) wide shm entry
and correctly read the array by type signature.
This type is msg safe.
'''
shm_name: str # this servers as a "key" value
shm_first_index_name: str
shm_last_index_name: str
dtype_descr: tuple
size: int # in struct-array index / row terms
# TODO: use nptyping here on dtypes
@property
def dtype(self) -> list[tuple[str, str, tuple[int, ...]]]:
return np.dtype(
list(
map(tuple, self.dtype_descr)
)
).descr
def as_msg(self):
return self.to_dict()
@classmethod
def from_msg(cls, msg: dict) -> NDToken:
if isinstance(msg, NDToken):
return msg
# TODO: native struct decoding
# return _token_dec.decode(msg)
msg['dtype_descr'] = tuple(map(tuple, msg['dtype_descr']))
return NDToken(**msg)
# _token_dec = msgspec.msgpack.Decoder(NDToken)
# TODO: this api?
# _known_tokens = tractor.ActorVar('_shm_tokens', {})
# _known_tokens = tractor.ContextStack('_known_tokens', )
# _known_tokens = trio.RunVar('shms', {})
# TODO: this should maybe be provided via
# a `.trionics.maybe_open_context()` wrapper factory?
# process-local store of keys to tokens
_known_tokens: dict[str, NDToken] = {}
def get_shm_token(key: str) -> NDToken | None:
'''
Convenience func to check if a token
for the provided key is known by this process.
Returns either the ``numpy`` token or a string for a shared list.
'''
return _known_tokens.get(key)
def _make_token(
key: str,
size: int,
dtype: np.dtype,
) -> NDToken:
'''
Create a serializable token that can be used
to access a shared array.
'''
return NDToken(
shm_name=key,
shm_first_index_name=key + "_first",
shm_last_index_name=key + "_last",
dtype_descr=tuple(np.dtype(dtype).descr),
size=size,
)
class ShmArray:
'''
A shared memory ``numpy.ndarray`` API.
An underlying shared memory buffer is allocated based on
a user specified ``numpy.ndarray``. This fixed size array
can be read and written to by pushing data both onto the "front"
or "back" of a set index range. The indexes for the "first" and
"last" index are themselves stored in shared memory (accessed via
``SharedInt`` interfaces) values such that multiple processes can
interact with the same array using a synchronized-index.
'''
def __init__(
self,
shmarr: np.ndarray,
first: SharedInt,
last: SharedInt,
shm: SharedMemory,
# readonly: bool = True,
) -> None:
self._array = shmarr
# indexes for first and last indices corresponding
# to fille data
self._first = first
self._last = last
self._len = len(shmarr)
self._shm = shm
self._post_init: bool = False
# pushing data does not write the index (aka primary key)
self._write_fields: list[str] | None = None
dtype = shmarr.dtype
if dtype.fields:
self._write_fields = list(shmarr.dtype.fields.keys())[1:]
# TODO: ringbuf api?
@property
def _token(self) -> NDToken:
return NDToken(
shm_name=self._shm.name,
shm_first_index_name=self._first._shm.name,
shm_last_index_name=self._last._shm.name,
dtype_descr=tuple(self._array.dtype.descr),
size=self._len,
)
@property
def token(self) -> dict:
"""Shared memory token that can be serialized and used by
another process to attach to this array.
"""
return self._token.as_msg()
@property
def index(self) -> int:
return self._last.value % self._len
@property
def array(self) -> np.ndarray:
'''
Return an up-to-date ``np.ndarray`` view of the
so-far-written data to the underlying shm buffer.
'''
a = self._array[self._first.value:self._last.value]
# first, last = self._first.value, self._last.value
# a = self._array[first:last]
# TODO: eventually comment this once we've not seen it in the
# wild in a long time..
# XXX: race where first/last indexes cause a reader
# to load an empty array..
if len(a) == 0 and self._post_init:
raise RuntimeError('Empty array race condition hit!?')
# breakpoint()
return a
def ustruct(
self,
fields: Optional[list[str]] = None,
# type that all field values will be cast to in the returned
# view.
common_dtype: np.dtype = np.float64, # type: ignore
) -> np.ndarray:
array = self._array
if fields:
selection = array[fields]
# fcount = len(fields)
else:
selection = array
# fcount = len(array.dtype.fields)
# XXX: manual ``.view()`` attempt that also doesn't work.
# uview = selection.view(
# dtype='<f16',
# ).reshape(-1, 4, order='A')
# assert len(selection) == len(uview)
u = rfn.structured_to_unstructured(
selection,
# dtype=float,
copy=True,
)
# unstruct = np.ndarray(u.shape, dtype=a.dtype, buffer=shm.buf)
# array[:] = a[:]
return u
# return ShmArray(
# shmarr=u,
# first=self._first,
# last=self._last,
# shm=self._shm
# )
def last(
self,
length: int = 1,
) -> np.ndarray:
'''
Return the last ``length``'s worth of ("row") entries from the
array.
'''
return self.array[-length:]
def push(
self,
data: np.ndarray,
field_map: Optional[dict[str, str]] = None,
prepend: bool = False,
update_first: bool = True,
start: Optional[int] = None,
) -> int:
'''
Ring buffer like "push" to append data
into the buffer and return updated "last" index.
NB: no actual ring logic yet to give a "loop around" on overflow
condition, lel.
'''
length = len(data)
if prepend:
index = (start or self._first.value) - length
if index < 0:
raise ValueError(
f'Array size of {self._len} was overrun during prepend.\n'
f'You have passed {abs(index)} too many datums.'
)
else:
index = start if start is not None else self._last.value
end = index + length
if field_map:
src_names, dst_names = zip(*field_map.items())
else:
dst_names = src_names = self._write_fields
try:
self._array[
list(dst_names)
][index:end] = data[list(src_names)][:]
# NOTE: there was a race here between updating
# the first and last indices and when the next reader
# tries to access ``.array`` (which due to the index
# overlap will be empty). Pretty sure we've fixed it now
# but leaving this here as a reminder.
if prepend and update_first and length:
assert index < self._first.value
if (
index < self._first.value
and update_first
):
assert prepend, 'prepend=True not passed but index decreased?'
self._first.value = index
elif not prepend:
self._last.value = end
self._post_init = True
return end
except ValueError as err:
if field_map:
raise
# should raise if diff detected
self.diff_err_fields(data)
raise err
def diff_err_fields(
self,
data: np.ndarray,
) -> None:
# reraise with any field discrepancy
our_fields, their_fields = (
set(self._array.dtype.fields),
set(data.dtype.fields),
)
only_in_ours = our_fields - their_fields
only_in_theirs = their_fields - our_fields
if only_in_ours:
raise TypeError(
f"Input array is missing field(s): {only_in_ours}"
)
elif only_in_theirs:
raise TypeError(
f"Input array has unknown field(s): {only_in_theirs}"
)
# TODO: support "silent" prepends that don't update ._first.value?
def prepend(
self,
data: np.ndarray,
) -> int:
end = self.push(data, prepend=True)
assert end
def close(self) -> None:
self._first._shm.close()
self._last._shm.close()
self._shm.close()
def destroy(self) -> None:
if _USE_POSIX:
# We manually unlink to bypass all the "resource tracker"
# nonsense meant for non-SC systems.
shm_unlink(self._shm.name)
self._first.destroy()
self._last.destroy()
def flush(self) -> None:
# TODO: flush to storage backend like markestore?
...
def open_shm_ndarray(
key: Optional[str] = None,
size: int = int(2 ** 10),
dtype: np.dtype | None = None,
append_start_index: int = 0,
readonly: bool = False,
) -> ShmArray:
'''
Open a memory shared ``numpy`` using the standard library.
This call unlinks (aka permanently destroys) the buffer on teardown
and thus should be used from the parent-most accessor (process).
'''
# create new shared mem segment for which we
# have write permission
a = np.zeros(size, dtype=dtype)
a['index'] = np.arange(len(a))
shm = SharedMemory(
name=key,
create=True,
size=a.nbytes
)
array = np.ndarray(
a.shape,
dtype=a.dtype,
buffer=shm.buf
)
array[:] = a[:]
array.setflags(write=int(not readonly))
token = _make_token(
key=key,
size=size,
dtype=dtype,
)
# create single entry arrays for storing an first and last indices
first = SharedInt(
shm=SharedMemory(
name=token.shm_first_index_name,
create=True,
size=4, # std int
)
)
last = SharedInt(
shm=SharedMemory(
name=token.shm_last_index_name,
create=True,
size=4, # std int
)
)
# Start the "real-time" append-updated (or "pushed-to") section
# after some start index: ``append_start_index``. This allows appending
# from a start point in the array which isn't the 0 index and looks
# something like,
# -------------------------
# | | i
# _________________________
# <-------------> <------->
# history real-time
#
# Once fully "prepended", the history section will leave the
# ``ShmArray._start.value: int = 0`` and the yet-to-be written
# real-time section will start at ``ShmArray.index: int``.
# this sets the index to 3/4 of the length of the buffer
# leaving a "days worth of second samples" for the real-time
# section.
last.value = first.value = append_start_index
shmarr = ShmArray(
array,
first,
last,
shm,
)
assert shmarr._token == token
_known_tokens[key] = shmarr.token
# "unlink" created shm on process teardown by
# pushing teardown calls onto actor context stack
stack = tractor.current_actor().lifetime_stack
stack.callback(shmarr.close)
stack.callback(shmarr.destroy)
return shmarr
def attach_shm_ndarray(
token: tuple[str, str, tuple[str, str]],
readonly: bool = True,
) -> ShmArray:
'''
Attach to an existing shared memory array previously
created by another process using ``open_shared_array``.
No new shared mem is allocated but wrapper types for read/write
access are constructed.
'''
token = NDToken.from_msg(token)
key = token.shm_name
if key in _known_tokens:
assert NDToken.from_msg(_known_tokens[key]) == token, "WTF"
# XXX: ugh, looks like due to the ``shm_open()`` C api we can't
# actually place files in a subdir, see discussion here:
# https://stackoverflow.com/a/11103289
# attach to array buffer and view as per dtype
_err: Optional[Exception] = None
for _ in range(3):
try:
shm = SharedMemory(
name=key,
create=False,
)
break
except OSError as oserr:
_err = oserr
time.sleep(0.1)
else:
if _err:
raise _err
shmarr = np.ndarray(
(token.size,),
dtype=token.dtype,
buffer=shm.buf
)
shmarr.setflags(write=int(not readonly))
first = SharedInt(
shm=SharedMemory(
name=token.shm_first_index_name,
create=False,
size=4, # std int
),
)
last = SharedInt(
shm=SharedMemory(
name=token.shm_last_index_name,
create=False,
size=4, # std int
),
)
# make sure we can read
first.value
sha = ShmArray(
shmarr,
first,
last,
shm,
)
# read test
sha.array
# Stash key -> token knowledge for future queries
# via `maybe_opepn_shm_array()` but only after we know
# we can attach.
if key not in _known_tokens:
_known_tokens[key] = token
# "close" attached shm on actor teardown
tractor.current_actor().lifetime_stack.callback(sha.close)
return sha
def maybe_open_shm_ndarray(
key: str, # unique identifier for segment
# from ``open_shm_array()``
size: int = int(2 ** 10), # array length in index terms
dtype: np.dtype | None = None,
append_start_index: int = 0,
readonly: bool = True,
) -> tuple[ShmArray, bool]:
'''
Attempt to attach to a shared memory block using a "key" lookup
to registered blocks in the users overall "system" registry
(presumes you don't have the block's explicit token).
This function is meant to solve the problem of discovering whether
a shared array token has been allocated or discovered by the actor
running in **this** process. Systems where multiple actors may seek
to access a common block can use this function to attempt to acquire
a token as discovered by the actors who have previously stored
a "key" -> ``NDToken`` map in an actor local (aka python global)
variable.
If you know the explicit ``NDToken`` for your memory segment instead
use ``attach_shm_array``.
'''
try:
# see if we already know this key
token = _known_tokens[key]
return (
attach_shm_ndarray(
token=token,
readonly=readonly,
),
False, # not newly opened
)
except KeyError:
log.warning(f"Could not find {key} in shms cache")
if dtype:
token = _make_token(
key,
size=size,
dtype=dtype,
)
else:
try:
return (
attach_shm_ndarray(
token=token,
readonly=readonly,
),
False,
)
except FileNotFoundError:
log.warning(f"Could not attach to shm with token {token}")
# This actor does not know about memory
# associated with the provided "key".
# Attempt to open a block and expect
# to fail if a block has been allocated
# on the OS by someone else.
return (
open_shm_ndarray(
key=key,
size=size,
dtype=dtype,
append_start_index=append_start_index,
readonly=readonly,
),
True,
)
class ShmList(ShareableList):
'''
Carbon copy of ``.shared_memory.ShareableList`` with a few
enhancements:
- readonly mode via instance var flag `._readonly: bool`
- ``.__getitem__()`` accepts ``slice`` inputs
- exposes the underlying buffer "name" as a ``.key: str``
'''
def __init__(
self,
sequence: list | None = None,
*,
name: str | None = None,
readonly: bool = True
) -> None:
self._readonly = readonly
self._key = name
return super().__init__(
sequence=sequence,
name=name,
)
@property
def key(self) -> str:
return self._key
@property
def readonly(self) -> bool:
return self._readonly
def __setitem__(
self,
position,
value,
) -> None:
# mimick ``numpy`` error
if self._readonly:
raise ValueError('assignment destination is read-only')
return super().__setitem__(position, value)
def __getitem__(
self,
indexish,
) -> list:
# NOTE: this is a non-writeable view (copy?) of the buffer
# in a new list instance.
if isinstance(indexish, slice):
return list(self)[indexish]
return super().__getitem__(indexish)
# TODO: should we offer a `.array` and `.push()` equivalent
# to the `ShmArray`?
# currently we have the following limitations:
# - can't write slices of input using traditional slice-assign
# syntax due to the ``ShareableList.__setitem__()`` implementation.
# - ``list(shmlist)`` returns a non-mutable copy instead of
# a writeable view which would be handier numpy-style ops.
def open_shm_list(
key: str,
sequence: list | None = None,
size: int = int(2 ** 10),
dtype: float | int | bool | str | bytes | None = float,
readonly: bool = True,
) -> ShmList:
if sequence is None:
default = {
float: 0.,
int: 0,
bool: True,
str: 'doggy',
None: None,
}[dtype]
sequence = [default] * size
shml = ShmList(
sequence=sequence,
name=key,
readonly=readonly,
)
# "close" attached shm on actor teardown
try:
actor = tractor.current_actor()
actor.lifetime_stack.callback(shml.shm.close)
actor.lifetime_stack.callback(shml.shm.unlink)
except RuntimeError:
log.warning('tractor runtime not active, skipping teardown steps')
return shml
def attach_shm_list(
key: str,
readonly: bool = False,
) -> ShmList:
return ShmList(
name=key,
readonly=readonly,
)

View File

@ -133,12 +133,12 @@ async def gather_contexts(
# deliver control once all managers have started up
await all_entered.wait()
# NOTE: order *should* be preserved in the output values
# since ``dict``s are now implicitly ordered.
try:
yield tuple(unwrapped.values())
# we don't need a try/finally since cancellation will be triggered
# by the surrounding nursery on error.
finally:
# NOTE: this is ABSOLUTELY REQUIRED to avoid
# the following wacky bug:
# <tractorbugurlhere>
parent_exit.set()