[Python-Dev] RFC: PEP 445: Add new APIs to customize Python memory allocators

[Antoine Pitrou]

Le Tue, 18 Jun 2013 22:40:49 +0200,
Victor Stinner <victor.stinner at gmail.com> a écrit :
> 
> Other changes
> -------------
> 
[...]
> 
> * Configure external libraries like zlib or OpenSSL to allocate memory
>   using ``PyMem_RawMalloc()``

Why so, and is it done by default?

> Only one get/set function for block allocators
> ----------------------------------------------
> 
> Replace the 6 functions:
> 
> * ``void PyMem_GetRawAllocator(PyMemBlockAllocator *allocator)``
> * ``void PyMem_GetAllocator(PyMemBlockAllocator *allocator)``
> * ``void PyObject_GetAllocator(PyMemBlockAllocator *allocator)``
> * ``void PyMem_SetRawAllocator(PyMemBlockAllocator *allocator)``
> * ``void PyMem_SetAllocator(PyMemBlockAllocator *allocator)``
> * ``void PyObject_SetAllocator(PyMemBlockAllocator *allocator)``
> 
> with 2 functions with an additional *domain* argument:
> 
> * ``int PyMem_GetBlockAllocator(int domain, PyMemBlockAllocator
> *allocator)``
> * ``int PyMem_SetBlockAllocator(int domain, PyMemBlockAllocator
> *allocator)``

I would much prefer this solution.

> Drawback: the caller has to check if the result is 0, or handle the
> error.

Or you can just call Py_FatalError() if the domain is invalid.

> If an hook is used to the track memory usage, the ``malloc()`` memory
> will not be seen. Remaining ``malloc()`` may allocate a lot of memory
> and so would be missed in reports.

A lot of memory? In main()?

Regards

Antoine.