wehub-resource-sync
112 lines
4.6 KiB
Python
112 lines
4.6 KiB
Python
import uuid
|
|
from typing import Any, Optional
|
|
|
|
from ray.experimental.channel.common import ChannelInterface
|
|
|
|
|
|
class CachedChannel(ChannelInterface):
|
|
"""
|
|
CachedChannel wraps an inner channel and caches the data read from it until
|
|
`num_reads` reads have completed. If inner channel is None, the data
|
|
is written to serialization context and retrieved from there. This is useful
|
|
when passing data within the same actor and a shared memory channel can be
|
|
avoided.
|
|
|
|
Args:
|
|
num_reads: The number of reads from this channel that must happen before
|
|
writing again. Readers must be methods of the same actor.
|
|
inner_channel: The inner channel to cache data from. If None, the data is
|
|
read from the serialization context.
|
|
_channel_id: The unique ID for the channel. If None, a new ID is generated.
|
|
"""
|
|
|
|
def __init__(
|
|
self,
|
|
num_reads: int,
|
|
inner_channel: Optional[ChannelInterface] = None,
|
|
_channel_id: Optional[str] = None,
|
|
):
|
|
assert num_reads > 0, "num_reads must be greater than 0."
|
|
self._num_reads = num_reads
|
|
self._inner_channel = inner_channel
|
|
# Generate a unique ID for the channel. The writer and reader will use
|
|
# this ID to store and retrieve data from the _SerializationContext.
|
|
self._channel_id = _channel_id
|
|
if self._channel_id is None:
|
|
self._channel_id = str(uuid.uuid4())
|
|
|
|
def ensure_registered_as_writer(self) -> None:
|
|
if self._inner_channel is not None:
|
|
self._inner_channel.ensure_registered_as_writer()
|
|
|
|
def ensure_registered_as_reader(self) -> None:
|
|
if self._inner_channel is not None:
|
|
self._inner_channel.ensure_registered_as_reader()
|
|
|
|
def __reduce__(self):
|
|
return CachedChannel, (
|
|
self._num_reads,
|
|
self._inner_channel,
|
|
self._channel_id,
|
|
)
|
|
|
|
def __str__(self) -> str:
|
|
return (
|
|
f"CachedChannel(channel_id={self._channel_id}, "
|
|
f"num_reads={self._num_reads}), "
|
|
f"inner_channel={self._inner_channel})"
|
|
)
|
|
|
|
def write(self, value: Any, timeout: Optional[float] = None):
|
|
self.ensure_registered_as_writer()
|
|
# TODO: better organize the imports
|
|
from ray.experimental.channel import ChannelContext
|
|
|
|
if self._inner_channel is not None:
|
|
self._inner_channel.write(value, timeout)
|
|
return
|
|
|
|
# Otherwise no need to check timeout as the operation is non-blocking.
|
|
|
|
# Because both the reader and writer are in the same worker process,
|
|
# we can directly store the data in the context instead of storing
|
|
# it in the channel object. This removes the serialization overhead of `value`.
|
|
ctx = ChannelContext.get_current().serialization_context
|
|
ctx.set_data(self._channel_id, value, self._num_reads)
|
|
|
|
def read(self, timeout: Optional[float] = None) -> Any:
|
|
self.ensure_registered_as_reader()
|
|
# TODO: better organize the imports
|
|
from ray.experimental.channel import ChannelContext
|
|
|
|
ctx = ChannelContext.get_current().serialization_context
|
|
if ctx.has_data(self._channel_id):
|
|
# No need to check timeout as the operation is non-blocking.
|
|
return ctx.get_data(self._channel_id)
|
|
|
|
assert (
|
|
self._inner_channel is not None
|
|
), "Cannot read from the serialization context while inner channel is None."
|
|
value = self._inner_channel.read(timeout)
|
|
ctx.set_data(self._channel_id, value, self._num_reads)
|
|
# NOTE: Currently we make a contract with Compiled Graph users that the
|
|
# channel results should not be mutated by the actor methods.
|
|
# When the user needs to modify the channel results, they should
|
|
# make a copy of the channel results and modify the copy.
|
|
# This is the same contract as used in IntraProcessChannel.
|
|
# This contract is NOT enforced right now in either case.
|
|
# TODO(rui): introduce a flag to control the behavior:
|
|
# for example, by default we make a deep copy of the channel
|
|
# result, but the user can turn off the deep copy for performance
|
|
# improvements.
|
|
# https://github.com/ray-project/ray/issues/47409
|
|
return ctx.get_data(self._channel_id)
|
|
|
|
def close(self) -> None:
|
|
from ray.experimental.channel import ChannelContext
|
|
|
|
if self._inner_channel is not None:
|
|
self._inner_channel.close()
|
|
ctx = ChannelContext.get_current().serialization_context
|
|
ctx.reset_data(self._channel_id)
|