Experimental Actor Pool (#6055)

* mod_table

* Example fix for gallery

* lint

* nit

* nit

* fix

* gallery

* remove table for now

* training, object store, tune, actors, advanced

* start tf code

* first cut tf

* yapf

* pytorch

* add torch example

* torch

* parallel

* tune

* tuning

* reviewsready

* finetune

* fix

* move_code

* update conf

* compile

* init hyperparameter

* Start images

* overview

* extra

* fix

* works

* update-ps-example

* param_actor

* fix

* examples

* simple

* simplify_pong

* flake8 and run hyperopt

* add comments

* add comments

* add suggestion

* add suggestion

* suggestions

* add suggestion

* add suggestions

* fixed in wrong area

* last edit

* finish changes

* add line

* format

* reset

* tests and docs

* fix tests

* bazelify

Co-authored-by: Richard Liaw <rliaw@berkeley.edu>
This commit is contained in:
zhu-eric
2019-12-26 14:35:10 -08:00
committed by Richard Liaw
parent 0dd8a60679
commit 65297e65f0
7 changed files with 406 additions and 8 deletions
+2 -1
View File
@@ -6,6 +6,7 @@ from .gcs_flush_policy import (set_flushing_policy, GcsFlushPolicy,
SimpleGcsFlushPolicy)
from .named_actors import get_actor, register_actor
from .api import get, wait
from .actor_pool import ActorPool
from .dynamic_resources import set_resource
@@ -18,5 +19,5 @@ def TensorFlowVariables(*args, **kwargs):
__all__ = [
"TensorFlowVariables", "get_actor", "register_actor", "get", "wait",
"set_flushing_policy", "GcsFlushPolicy", "SimpleGcsFlushPolicy",
"set_resource"
"set_resource", "ActorPool"
]
+216
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@@ -0,0 +1,216 @@
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import ray
class ActorPool(object):
"""Utility class to operate on a fixed pool of actors.
Arguments:
actors (list): List of Ray actor handles to use in this pool.
Examples:
>>> a1, a2 = Actor.remote(), Actor.remote()
>>> pool = ActorPool([a1, a2])
>>> print(pool.map(lambda a, v: a.double.remote(v), [1, 2, 3, 4]))
[2, 4, 6, 8]
"""
def __init__(self, actors):
# actors to be used
self._idle_actors = list(actors)
# get actor from future
self._future_to_actor = {}
# get future from index
self._index_to_future = {}
# next task to do
self._next_task_index = 0
# next task to return
self._next_return_index = 0
# next work depending when actors free
self._pending_submits = []
def map(self, fn, values):
"""Apply the given function in parallel over the actors and values.
This returns an ordered iterator that will return results of the map
as they finish. Note that you must iterate over the iterator to force
the computation to finish.
Arguments:
fn (func): Function that takes (actor, value) as argument and
returns an ObjectID computing the result over the value. The
actor will be considered busy until the ObjectID completes.
values (list): List of values that fn(actor, value) should be
applied to.
Returns:
Iterator over results from applying fn to the actors and values.
Examples:
>>> pool = ActorPool(...)
>>> print(pool.map(lambda a, v: a.double.remote(v), [1, 2, 3, 4]))
[2, 4, 6, 8]
"""
for v in values:
self.submit(fn, v)
while self.has_next():
yield self.get_next()
def map_unordered(self, fn, values):
"""Similar to map(), but returning an unordered iterator.
This returns an unordered iterator that will return results of the map
as they finish. This can be more efficient that map() if some results
take longer to compute than others.
Arguments:
fn (func): Function that takes (actor, value) as argument and
returns an ObjectID computing the result over the value. The
actor will be considered busy until the ObjectID completes.
values (list): List of values that fn(actor, value) should be
applied to.
Returns:
Iterator over results from applying fn to the actors and values.
Examples:
>>> pool = ActorPool(...)
>>> print(pool.map(lambda a, v: a.double.remote(v), [1, 2, 3, 4]))
[6, 2, 4, 8]
"""
for v in values:
self.submit(fn, v)
while self.has_next():
yield self.get_next_unordered()
def submit(self, fn, value):
"""Schedule a single task to run in the pool.
This has the same argument semantics as map(), but takes on a single
value instead of a list of values. The result can be retrieved using
get_next() / get_next_unordered().
Arguments:
fn (func): Function that takes (actor, value) as argument and
returns an ObjectID computing the result over the value. The
actor will be considered busy until the ObjectID completes.
value (object): Value to compute a result for.
Examples:
>>> pool = ActorPool(...)
>>> pool.submit(lambda a, v: a.double.remote(v), 1)
>>> pool.submit(lambda a, v: a.double.remote(v), 2)
>>> print(pool.get_next(), pool.get_next())
2, 4
"""
if self._idle_actors:
actor = self._idle_actors.pop()
future = fn(actor, value)
self._future_to_actor[future] = (self._next_task_index, actor)
self._index_to_future[self._next_task_index] = future
self._next_task_index += 1
else:
self._pending_submits.append((fn, value))
def has_next(self):
"""Returns whether there are any pending results to return.
Returns:
True if there are any pending results not yet returned.
Examples:
>>> pool = ActorPool(...)
>>> pool.submit(lambda a, v: a.double.remote(v), 1)
>>> print(pool.has_next())
True
>>> print(pool.get_next())
2
>>> print(pool.has_next())
False
"""
return bool(self._future_to_actor)
def get_next(self, timeout=None):
"""Returns the next pending result in order.
This returns the next result produced by submit(), blocking for up to
the specified timeout until it is available.
Returns:
The next result.
Raises:
TimeoutError if the timeout is reached.
Examples:
>>> pool = ActorPool(...)
>>> pool.submit(lambda a, v: a.double.remote(v), 1)
>>> print(pool.get_next())
2
"""
if not self.has_next():
raise StopIteration("No more results to get")
if self._next_return_index >= self._next_task_index:
raise ValueError("It is not allowed to call get_next() after "
"get_next_unordered().")
future = self._index_to_future[self._next_return_index]
if timeout is not None:
res, _ = ray.wait([future], timeout=timeout)
if not res:
raise TimeoutError("Timed out waiting for result")
del self._index_to_future[self._next_return_index]
self._next_return_index += 1
i, a = self._future_to_actor.pop(future)
self._return_actor(a)
return ray.get(future)
def get_next_unordered(self, timeout=None):
"""Returns any of the next pending results.
This returns some result produced by submit(), blocking for up to
the specified timeout until it is available. Unlike get_next(), the
results are not always returned in same order as submitted, which can
improve performance.
Returns:
The next result.
Raises:
TimeoutError if the timeout is reached.
Examples:
>>> pool = ActorPool(...)
>>> pool.submit(lambda a, v: a.double.remote(v), 1)
>>> pool.submit(lambda a, v: a.double.remote(v), 2)
>>> print(pool.get_next_unordered())
4
>>> print(pool.get_next_unordered())
2
"""
if not self.has_next():
raise StopIteration("No more results to get")
# TODO(ekl) bulk wait for performance
res, _ = ray.wait(
list(self._future_to_actor), num_returns=1, timeout=timeout)
if res:
[future] = res
else:
raise TimeoutError("Timed out waiting for result")
i, a = self._future_to_actor.pop(future)
self._return_actor(a)
del self._index_to_future[i]
self._next_return_index = max(self._next_return_index, i + 1)
return ray.get(future)
def _return_actor(self, actor):
self._idle_actors.append(actor)
if self._pending_submits:
self.submit(*self._pending_submits.pop(0))
+9 -7
View File
@@ -32,18 +32,20 @@ class SimpleGcsFlushPolicy(GcsFlushPolicy):
"""A simple policy with constant flush rate, after a warmup period.
Example policy values:
flush_when_at_least_bytes 2GB
flush_period_secs 10s
flush_num_entries_each_time 10k
This means
(1) If the GCS shard uses less than 2GB of memory, no flushing would take
place. This should cover most Ray runs.
(2) The GCS shard will only honor a flush request, if it's issued after 10
seconds since the last processed flush. In particular this means it's
okay for the Monitor to issue requests more frequently than this param.
This means: (1) If the GCS shard uses less than 2GB of memory,
no flushing would take place. This should cover most Ray runs. (2) The
GCS shard will only honor a flush request, if it's issued after 10
seconds since the last processed flush. In particular this means it's
okay for the Monitor to issue requests more frequently than this param.
(3) When processing a flush, the shard will flush at most 10k entries.
This is to control the latency of each request.
This is to control the latency of each request.
Note, flush rate == (flush period) * (num entries each time). So
applications that have a heavier GCS load can tune these params.
+8
View File
@@ -6,6 +6,14 @@ py_test(
deps = ["//:ray_lib"],
)
py_test(
name = "test_actor_pool",
size = "small",
srcs = ["test_actor_pool.py"],
tags = ["exclusive"],
deps = ["//:ray_lib"],
)
py_test(
name = "test_actor_resources",
size = "medium",
+148
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@@ -0,0 +1,148 @@
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import time
import pytest
import ray
from ray.experimental import ActorPool
@pytest.fixture
def init():
ray.init(num_cpus=4)
yield
ray.shutdown()
def test_get_next(init):
@ray.remote
class MyActor(object):
def __init__(self):
pass
def f(self, x):
return x + 1
def double(self, x):
return 2 * x
actors = [MyActor.remote() for _ in range(4)]
pool = ActorPool(actors)
for i in range(5):
pool.submit(lambda a, v: a.f.remote(v), i)
assert pool.get_next() == i + 1
def test_get_next_unordered(init):
@ray.remote
class MyActor(object):
def __init__(self):
pass
def f(self, x):
return x + 1
def double(self, x):
return 2 * x
actors = [MyActor.remote() for _ in range(4)]
pool = ActorPool(actors)
total = []
for i in range(5):
pool.submit(lambda a, v: a.f.remote(v), i)
while pool.has_next():
total += [pool.get_next_unordered()]
assert all(elem in [1, 2, 3, 4, 5] for elem in total)
def test_map(init):
@ray.remote
class MyActor(object):
def __init__(self):
pass
def f(self, x):
return x + 1
def double(self, x):
return 2 * x
actors = [MyActor.remote() for _ in range(4)]
pool = ActorPool(actors)
index = 0
for v in pool.map(lambda a, v: a.double.remote(v), range(5)):
assert v == 2 * index
index += 1
def test_map_unordered(init):
@ray.remote
class MyActor(object):
def __init__(self):
pass
def f(self, x):
return x + 1
def double(self, x):
return 2 * x
actors = [MyActor.remote() for _ in range(4)]
pool = ActorPool(actors)
total = []
for v in pool.map(lambda a, v: a.double.remote(v), range(5)):
total += [v]
assert all(elem in [0, 2, 4, 6, 8] for elem in total)
def test_get_next_timeout(init):
@ray.remote
class MyActor(object):
def __init__(self):
pass
def f(self, x):
while (True):
x = x + 1
time.sleep(1)
return None
def double(self, x):
return 2 * x
actors = [MyActor.remote() for _ in range(4)]
pool = ActorPool(actors)
pool.submit(lambda a, v: a.f.remote(v), 0)
with pytest.raises(TimeoutError):
pool.get_next_unordered(5)
def test_get_next_unordered_timeout(init):
@ray.remote
class MyActor(object):
def __init__(self):
pass
def f(self, x):
while (True):
x + 1
time.sleep(1)
return
def double(self, x):
return 2 * x
actors = [MyActor.remote() for _ in range(4)]
pool = ActorPool(actors)
pool.submit(lambda a, v: a.f.remote(v), 0)
with pytest.raises(TimeoutError):
pool.get_next_unordered(5)