releasing memory to malloc

[Paul Rubin]

    Is there any way to get Python to release memory back to the
    C allocator? I'm currently running a script that goes through
    the following steps:

    1) Creates a very large number of Python objects to produce
    a relatively small data structure that sits in a C extension.
    The Python objects consume quite a bit of memory.

    2) Releases all the Python objects.

    3) Invokes a function of said C extension for further
    processing. This step needs as much memory as possible.
    ...

   I happen to have the code for the C library in question, but I
   don't think this is the way to go in general.  If there's a way to
   get Python to give memory back to the C allocator I can avoid
   touching the library at all.

A cave-man approach might be to fork a new process after step 1, pass
the small data structure to it, and have the old process exit
(releasing all its memory back to the OS).  The new process then
carries out the remaining steps.