Fix race condition in bolt connection pool - #1346
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The pool tries to acquire an idle connection first. If no idle connection is available, it puts itself into a queue waiting for another thread/task to return a connection before trying again. However, there is no protection against a connection being returned between the attempt to acquire an idle connection and the enqueuing. Therefore, it could happen that a thread waits indefinitely like this: Assume max pool size of 1 * T1 creates & acquires con1 * T2 checks for idle connections => None * T1 releases con1 * T2 acquires lock to be able to wait for the release event * T1 terminates * T2 times out waiting for Godot
robsdedude
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robsdedude
marked this pull request as ready for review
September 23, 2026 21:06
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The pool tries to acquire an idle connection first. If no idle connection is
available, it puts itself into a queue waiting for another thread/task to return
a connection before trying again.
However, there is no protection against a connection being returned between the
attempt to acquire an idle connection and the enqueuing. Therefore, it could
happen that a thread waits indefinitely like this:
Assume max pool size of 1
Closes: DRIVERS-578