What is GIL (Global Interpreter Lock) in python?

Mutex :
  • A mutex is a program object that allows multiple program threads to share the same resource, such as file access, but not simultaneously.
  • When a program is started, a mutex is created with a unique name.

GIL ( Global Interpreter Lock ) :
  • A global interpreter lock (GIL) is a mechanism used in computer language interpreters to synchronize the execution of threads so that only one native thread can execute at a time.
  • An interpreter that uses GIL always allows exactly one thread to execute at a time, even if run on a multi-core processor.
  • C Python has a gil.
  • GIL is a mutex that prevents multiple native threads from executing Python byte-codes at once.
  • This lock is necessary because C Python's memory management is not thread-safe.
  • The GIL is controversial because it prevents multi-threaded C Python programs from taking full advantage of multiprocessor systems in certain situations.

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