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Is there another race condition when a lock is released?
See original GitHub issueAs shown above, the step to release the lock is 1. Execute the UNLOCK script 2. Execute the _delete_signal function.
Consider a situation with two processes:
- Process 1 currently holds a lock.
- process 2 is ready to acquire the lock.
Now, suppose that the following sequence of events unfolds:
- process 2 executes the
SETNXcommand to obtain the lock but does not get it. - Process 1 executes the
UNLOCKscript to release the lock. - process 1 executes the
_delete_signalfunction. - process 2 executes the
BLPOPcommand. It then waits for a timeout to acquire the lock again, and that’s the problem.
So I wonder why there ended up with a _delete_signal function. Can you explain it a little bit?
I think this guy’s got the same problem. https://github.com/ionelmc/python-redis-lock/issues/58#issuecomment-348712157
Issue Analytics
- State:
- Created 4 years ago
- Comments:9 (6 by maintainers)
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But does it work or get stuck? Or are you just complaining about efficiency?
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