並行執行 (Concurrent Execution)

本章節描述的模組在程式的並行執行上提供支援。選擇要使用哪一個工具則取決於是執行什麼樣的任務（CPU 密集或 IO 密集）與偏好的開發風格（事件驅動協作式多工處理或搶占式多工處理）。以下為此章節總覽：

• threading --- Thread-based parallelism
  • Thread-Local Data
  • Thread Objects
  • Lock Objects
  • RLock 物件
  • Condition Objects
  • Semaphore Objects
    • Semaphore 範例
  • Event Objects
  • Timer Objects
  • Barrier Objects
  • Using locks, conditions, and semaphores in the with statement
• multiprocessing --- Process-based parallelism
  • 簡介
    • The Process class
    • Contexts and start methods
    • Exchanging objects between processes
    • Synchronization between processes
    • Sharing state between processes
    • Using a pool of workers
  • Reference
    • Process 與例外
    • Pipes and Queues
    • Miscellaneous
    • Connection Objects
    • Synchronization primitives
    • Shared ctypes Objects
      • The multiprocessing.sharedctypes module
    • Managers
      • Customized managers
      • Using a remote manager
    • Proxy Objects
      • Cleanup
    • Process Pools
    • Listeners and Clients
      • Address Formats
    • Authentication keys
    • Logging
    • The multiprocessing.dummy module
  • Programming guidelines
    • All start methods
    • The spawn and forkserver start methods
  • 範例
• multiprocessing.shared_memory --- Shared memory for direct access across processes
• The concurrent package
• concurrent.futures -- 啟動平行任務
  • Executor 物件
  • ThreadPoolExecutor
    • ThreadPoolExecutor 範例
  • ProcessPoolExecutor
    • ProcessPoolExecutor 範例
  • Future 物件
  • 模組函式
  • 例外類別
• subprocess --- Subprocess management
  • Using the subprocess Module
    • Frequently Used Arguments
    • Popen Constructor
    • 例外
  • Security Considerations
  • Popen Objects
  • Windows Popen Helpers
    • Windows Constants
  • Older high-level API
  • Replacing Older Functions with the subprocess Module
    • Replacing /bin/sh shell command substitution
    • Replacing shell pipeline
    • Replacing os.system()
    • Replacing the os.spawn family
    • Replacing os.popen(), os.popen2(), os.popen3()
    • Replacing functions from the popen2 module
  • Legacy Shell Invocation Functions
  • 註解
    • Converting an argument sequence to a string on Windows
    • Disabling use of vfork() or posix_spawn()
• sched --- Event scheduler
  • Scheduler Objects
• queue --- 同步佇列 (queue) class（類別）
  • 佇列物件
  • SimpleQueue 物件
• contextvars --- Context Variables
  • Context Variables
  • Manual Context Management
  • asyncio support

以下是支援部份上述服務的模組：

• _thread --- Low-level threading API