Improve parallel map API

This commit is contained in:
Andras Schmelczer 2022-06-30 16:54:01 +02:00
parent 5dc85905b4
commit 154cc52fa6
6 changed files with 94 additions and 84 deletions

View file

@ -103,7 +103,7 @@ def configure(
logger.info("Settings: configured ✅")
for k, v in get_context().to_flat_dict().items():
logger.info(f"🔩 {k}: {v}")
logger.info(f" ⚙️ {k}: {v}")
if not is_production and not disable_se4ml_banner:
logger.warning(

View file

@ -3,13 +3,13 @@ from typing import Iterable, List, TypeVar
T = TypeVar("T")
def chunk(values: Iterable[T], chunk_length: int) -> Iterable[T]:
assert chunk_length >= 1
def chunk(values: Iterable[T], chunk_size: int) -> Iterable[T]:
assert chunk_size >= 1
result: List[T] = []
for v in values:
result.append(v)
if len(result) == chunk_length:
if len(result) == chunk_size:
yield result
result = []

View file

@ -14,8 +14,9 @@ def get_config(
*,
function: Callable,
input_values: Union[Sequence, Iterable],
chunk_length: Optional[int],
chunk_size: Optional[int],
concurrency: Optional[int],
disable_logging: bool,
) -> ParallelMapConfiguration:
is_input_sequence = hasattr(input_values, "__len__")
@ -24,18 +25,18 @@ def get_config(
concurrency = len(os.sched_getaffinity(0))
assert concurrency >= 1, "At least one mapper process has to be created"
if chunk_length is None:
if chunk_size is None:
if is_input_sequence:
chunk_length = max(1, ceil(len(input_values) / concurrency / 10))
chunk_size = max(1, ceil(len(input_values) / concurrency / 10))
else:
raise ValueError(
"The argument for `values` does not implement `__len__`, therefore, you must provide a `chunk_length`"
"The argument for `values` does not implement `__len__`, therefore, you must provide a `chunk_size`"
)
assert chunk_length >= 1, "Chunks have to contain at least one element"
assert chunk_size >= 1, "Chunks have to contain at least one element"
chunk_count: Optional[int] = None
if is_input_sequence:
chunk_count = ceil(len(input_values) / chunk_length)
chunk_count = ceil(len(input_values) / chunk_size)
if chunk_count < concurrency:
logger.warning(
f"Limiting concurrency to {chunk_count} because there are only {chunk_count} chunks"
@ -47,16 +48,17 @@ def get_config(
input_length = len(input_values) if is_input_sequence else None
serialized_map_function = dill.dumps(function, byref=True, recurse=True)
logger.info("Parallel map: configured ✅")
config = ParallelMapConfiguration(
concurrency=concurrency,
chunk_count=chunk_count,
chunk_length=chunk_length,
chunk_size=chunk_size,
input_length=input_length,
serialized_map_function=serialized_map_function,
serialized_map_function=dill.dumps(function, byref=True, recurse=True),
function_name=function.__name__,
)
config.pretty_print()
if not disable_logging:
logger.info("Parallel map: configured ✅")
config.pretty_print()
return config

View file

@ -1,17 +1,8 @@
import multiprocessing as mp
import queue
from typing import (
Callable,
Iterable,
List,
Optional,
Sequence,
Tuple,
TypeVar,
overload,
)
from typing import Callable, Dict, Iterable, Optional, Sequence, TypeVar, overload
from tqdm.auto import tqdm
from tqdm.cli import tqdm
from ..chunk import chunk
from .get_config import get_config
@ -26,10 +17,11 @@ def parallel_map(
function: Callable[[T], V],
input_values: Sequence[T],
*,
chunk_length: Optional[int],
chunk_size: Optional[int],
concurrency: Optional[int],
disable_progress_bar: bool,
) -> List[V]:
disable_logging: bool,
unordered: Optional[bool],
) -> Iterable[V]:
...
@ -38,10 +30,11 @@ def parallel_map(
function: Callable[[T], V],
input_values: Iterable[T],
*,
chunk_length: int,
chunk_size: int,
concurrency: Optional[int],
disable_progress_bar: bool,
) -> List[V]:
disable_logging: bool,
unordered: Optional[bool],
) -> Iterable[V]:
...
@ -49,30 +42,32 @@ def parallel_map(
function,
input_values,
*,
chunk_length=None,
chunk_size=None,
concurrency=None,
disable_progress_bar=False,
disable_logging=False,
unordered=False,
):
config = get_config(
function=function,
input_values=input_values,
chunk_length=chunk_length,
chunk_size=chunk_size,
concurrency=concurrency,
disable_logging=disable_logging,
)
tqdm_options = dict(
desc=f"Parallel map {config.function_name}",
disable=disable_logging,
total=config.input_length,
miniters=1,
dynamic_ncols=True,
)
if config.concurrency == 1:
return [
function(v)
for v in tqdm(
input_values,
desc="Parallel map",
disable=disable_progress_bar,
total=config.input_length,
)
]
yield from (function(v) for v in tqdm(input_values, **tqdm_options))
return
start_methods = mp.get_all_start_methods()
ctx = mp.get_context("fork") if "fork" in start_methods else mp.get_context("spawn")
ctx = mp.get_context("spawn")
ctx.freeze_support()
input_queue = ctx.Queue(0 if config.chunk_count is None else config.chunk_count)
@ -81,7 +76,7 @@ def parallel_map(
processes = [
ctx.Process(
name=f"parallel_map_{i}",
name=f"parallel_map_{config.function_name}_{i}",
target=mapper_function,
kwargs=dict(
input_queue=input_queue,
@ -96,18 +91,15 @@ def parallel_map(
for p in processes:
p.start()
progress = tqdm(
desc="Parallel map",
disable=disable_progress_bar,
total=config.input_length,
)
progress = tqdm(**tqdm_options)
chunks = iter(chunk(enumerate(input_values), chunk_length=config.chunk_length))
indexed_results: List[Tuple[int, V]] = []
chunks = iter(chunk(enumerate(input_values), chunk_size=config.chunk_size))
indexed_results: Dict[int, V] = {}
next_output_index = 0
read_input_length = 0
is_iteration_over = False
try:
while not is_iteration_over or len(indexed_results) < read_input_length:
while not is_iteration_over or next_output_index < read_input_length:
if not is_iteration_over:
try:
next_chunk = next(chunks)
@ -118,10 +110,23 @@ def parallel_map(
try:
result_chunk = output_queue.get_nowait()
indexed_results.extend(result_chunk)
progress.update(len(result_chunk))
for index, value in result_chunk:
if unordered:
yield value
next_output_index += 1
else:
indexed_results[index] = value
if not unordered:
while next_output_index in indexed_results:
yield indexed_results[next_output_index]
del indexed_results[next_output_index]
next_output_index += 1
except queue.Empty:
pass
should_stop.set()
except KeyboardInterrupt:
for p in processes:
@ -134,7 +139,3 @@ def parallel_map(
output_queue.close()
progress.close()
results = [v for _, v in sorted(indexed_results)]
return results

View file

@ -10,13 +10,14 @@ logger = get_logger("parallel_map")
class ParallelMapConfiguration(BaseModel):
concurrency: int
chunk_count: Optional[int]
chunk_length: int
chunk_size: int
input_length: Optional[int]
serialized_map_function: bytes
function_name: str
def pretty_print(self, prefix=" ⚙️ "):
logger.info(f"{prefix} concurrency: {self.concurrency}")
logger.info(f"{prefix} chunk length: {self.chunk_length}")
logger.info(f"{prefix} chunk size: {self.chunk_size}")
logger.info(
f"{prefix} chunk count: {self.chunk_count if self.chunk_count else 'unknown'}"
)

View file

@ -1,5 +1,7 @@
import unittest
import pytest
from src.great_ai.utilities import parallel_map
COUNT = int(1e5) + 3
@ -10,7 +12,7 @@ class TestParallelMap(unittest.TestCase):
inputs = range(COUNT)
expected = [v**2 for v in range(COUNT)]
assert parallel_map(lambda v: v**2, inputs, concurrency=10) == expected
assert list(parallel_map(lambda v: v**2, inputs, concurrency=10)) == expected
def test_with_iterable(self) -> None:
from time import sleep
@ -23,38 +25,42 @@ class TestParallelMap(unittest.TestCase):
expected = [v**3 for v in range(10)]
assert (
parallel_map(lambda x: x**3, my_generator(), chunk_length=1) == expected
list(parallel_map(lambda x: x**3, my_generator(), chunk_size=1))
== expected
)
def test_simple_case_without_progress_bar(self) -> None:
inputs = range(COUNT)
expected = [v**2 for v in range(COUNT)]
self.assertEqual(
parallel_map(lambda v: v**2, inputs, disable_progress_bar=True), expected
assert (
list(parallel_map(lambda v: v**2, inputs, disable_logging=True))
== expected
)
def test_simple_case_invalid_values(self) -> None:
inputs = range(COUNT)
self.assertRaises(
AssertionError, parallel_map, lambda v: v**2, inputs, concurrency=0
)
self.assertRaises(
AssertionError, parallel_map, lambda v: v**2, inputs, chunk_length=0
)
with pytest.raises(AssertionError):
list(parallel_map(lambda v: v**2, inputs, concurrency=0))
with pytest.raises(AssertionError):
list(parallel_map(lambda v: v**2, inputs, chunk_size=0))
def test_no_op(self) -> None:
assert parallel_map(lambda v: v**2, [], disable_progress_bar=True) == []
self.assertEqual(
parallel_map(
lambda v: v**2, [], disable_progress_bar=True, chunk_length=100
),
[],
assert list(parallel_map(lambda v: v**2, [], disable_logging=True)) == []
assert (
list(
parallel_map(lambda v: v**2, [], disable_logging=True, chunk_size=100)
)
== []
)
self.assertEqual(
parallel_map(
lambda v: v**2, [], disable_progress_bar=True, concurrency=100
),
[],
assert (
list(
parallel_map(
lambda v: v**2, [], disable_logging=True, concurrency=100
)
)
== []
)