[New-bugs-announce] [issue24411] Drop redundant lock in queue.Queue methods qsize(), empty() and full()

[Andrew Svetlov]

New submission from Andrew Svetlov:

Now those methods use lock for querying queue size, like

    def qsize(self):
        with self.mutex:
            return self._qsize()

The lock is not necessary because thread context switch may be done *after* returning from mutex protected code but *before* getting result by calling side.

All three methods (qsize(), empty() and full()) gives *approximated value*, so getting rid of lock doesn't make it less stringent.

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components: Library (Lib)
messages: 245029
nosy: asvetlov
priority: low
severity: normal
status: open
title: Drop redundant lock in queue.Queue methods qsize(), empty() and full()
versions: Python 3.5, Python 3.6

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue24411>
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