Revision a7770f03 lib/mcpu.py
| b/lib/mcpu.py | ||
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return result |
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class _LockAttemptTimeoutStrategy(object):
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class LockAttemptTimeoutStrategy(object): |
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"""Class with lock acquire timeout strategy. |
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""" |
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__slots__ = [ |
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"_attempt",
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"_timeouts",
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"_random_fn", |
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"_start_time", |
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"_time_fn", |
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"_running_timeout", |
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] |
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_TIMEOUT_PER_ATTEMPT = _CalculateLockAttemptTimeouts() |
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def __init__(self, attempt=0, _time_fn=time.time, _random_fn=random.random):
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def __init__(self, _time_fn=time.time, _random_fn=random.random): |
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"""Initializes this class. |
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@type attempt: int |
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@param attempt: Current attempt number |
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@param _time_fn: Time function for unittests |
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@param _random_fn: Random number generator for unittests |
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""" |
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object.__init__(self) |
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if attempt < 0: |
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raise ValueError("Attempt must be zero or positive")
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self._attempt = attempt |
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self._timeouts = iter(self._TIMEOUT_PER_ATTEMPT) |
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self._time_fn = _time_fn |
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self._random_fn = _random_fn |
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try: |
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timeout = self._TIMEOUT_PER_ATTEMPT[attempt] |
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except IndexError: |
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# No more timeouts, do blocking acquire |
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timeout = None |
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self._running_timeout = locking.RunningTimeout(timeout, False, |
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_time_fn=_time_fn) |
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def NextAttempt(self): |
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"""Returns the strategy for the next attempt.
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"""Returns the timeout for the next attempt.
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""" |
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return _LockAttemptTimeoutStrategy(attempt=self._attempt + 1, |
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_time_fn=self._time_fn, |
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_random_fn=self._random_fn) |
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def CalcRemainingTimeout(self): |
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"""Returns the remaining timeout. |
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""" |
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timeout = self._running_timeout.Remaining() |
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try: |
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timeout = self._timeouts.next() |
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except StopIteration: |
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# No more timeouts, do blocking acquire |
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timeout = None |
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if timeout is not None: |
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# Add a small variation (-/+ 5%) to timeout. This helps in situations |
Also available in: Unified diff