test_multiprocessing.py 文件源码

def test_free_from_gc(self):
        # Check that freeing of blocks by the garbage collector doesn't deadlock
        # (issue #12352).
        # Make sure the GC is enabled, and set lower collection thresholds to
        # make collections more frequent (and increase the probability of
        # deadlock).
        if not gc.isenabled():
            gc.enable()
            self.addCleanup(gc.disable)
        thresholds = gc.get_threshold()
        self.addCleanup(gc.set_threshold, *thresholds)
        gc.set_threshold(10)

        # perform numerous block allocations, with cyclic references to make
        # sure objects are collected asynchronously by the gc
        for i in range(5000):
            a = multiprocessing.heap.BufferWrapper(1)
            b = multiprocessing.heap.BufferWrapper(1)
            # circular references
            a.buddy = b
            b.buddy = a

#
#
#