cpython: 6a0437adafbd (original) (raw)

Mercurial > cpython

changeset 84355:6a0437adafbd

Issue #17914: Use os.cpu_count() instead of multiprocessing.cpu_count() where applicable. [#17914]

Charles-François Natali cf.natali@gmail.com
date	Fri, 28 Jun 2013 19:25:45 +0200
parents	9046ef201591
children	34ff27b431d0
files	Doc/library/multiprocessing.rst Lib/concurrent/futures/process.py Lib/multiprocessing/pool.py Lib/test/regrtest.py
diffstat	4 files changed, 7 insertions(+), 13 deletions(-)[+] [-] Doc/library/multiprocessing.rst 2 Lib/concurrent/futures/process.py 2 Lib/multiprocessing/pool.py 8 Lib/test/regrtest.py 8

line wrap: on

line diff

--- a/Doc/library/multiprocessing.rst +++ b/Doc/library/multiprocessing.rst @@ -1664,7 +1664,7 @@ with the :class:Pool class. callbacks and has a parallel map implementation. processes is the number of worker processes to use. If processes is

None then the number returned by :func:cpu_count is used. If

None then the number returned by :func:os.cpu_count is used. If initializer is not None then each worker process will call initializer(*initargs) when it starts.

--- a/Lib/concurrent/futures/process.py +++ b/Lib/concurrent/futures/process.py @@ -331,7 +331,7 @@ class ProcessPoolExecutor(_base.Executor _check_system_limits() if max_workers is None:

       self._max_workers = multiprocessing.cpu_count()[](#l2.7)

       self._max_workers = os.cpu_count() or 1[](#l2.8)
   else:[](#l2.9)
       self._max_workers = max_workers[](#l2.10)

--- a/Lib/multiprocessing/pool.py +++ b/Lib/multiprocessing/pool.py @@ -17,10 +17,11 @@ import threading import queue import itertools import collections +import os import time import traceback -from multiprocessing import Process, cpu_count, TimeoutError +from multiprocessing import Process, TimeoutError from multiprocessing.util import Finalize, debug # @@ -147,10 +148,7 @@ class Pool(object): self._initargs = initargs if processes is None:

```
       try:[](#l3.20)
```

           processes = cpu_count()[](#l3.21)

       except NotImplementedError:[](#l3.22)

```
           processes = 1[](#l3.23)
```

       processes = os.cpu_count() or 1[](#l3.24)
   if processes < 1:[](#l3.25)
       raise ValueError("Number of processes must be at least 1")[](#l3.26)

--- a/Lib/test/regrtest.py +++ b/Lib/test/regrtest.py @@ -508,12 +508,8 @@ def main(tests=None, testdir=None, verbo elif o in ('-j', '--multiprocess'): use_mp = int(a) if use_mp <= 0:

```
           try:[](#l4.7)
```

               import multiprocessing[](#l4.8)

               # Use all cores + extras for tests that like to sleep[](#l4.9)

               use_mp = 2 + multiprocessing.cpu_count()[](#l4.10)

           except (ImportError, NotImplementedError):[](#l4.11)

```
               use_mp = 3[](#l4.12)
```

           # Use all cores + extras for tests that like to sleep[](#l4.13)

           use_mp = 2 + (os.cpu_count() or 1)[](#l4.14)
       if use_mp == 1:[](#l4.15)
           use_mp = None[](#l4.16)
   elif o == '--header':[](#l4.17)