fix(spanner): stop AsyncResultSetImpl producer when callback throws with a full buffer#13827
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fornwall wants to merge 5 commits into
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fix(spanner): stop AsyncResultSetImpl producer when callback throws with a full buffer#13827fornwall wants to merge 5 commits into
fornwall wants to merge 5 commits into
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…ith a full buffer When a user-supplied ReadyCallback throws an exception, CallbackRunnable sets executionException and cursorReturnedDoneOrException, but leaves the state at CONSUMING (shouldStop == false). If the producer was waiting for the callback to consume rows from a full buffer at that moment, it recomputed its stop condition solely from state.shouldStop and looped again: startCallbackWithBufferLatchIfNecessary refuses to restart the callback or re-arm bufferConsumptionLatch once cursorReturnedDoneOrException is set, so the await returned immediately on the already-drained latch. The result was an infinite busy-spin at 100% CPU, the delegate result set was never closed, and the ApiFuture returned by setCallback()/toListAsync() never completed. Include cursorReturnedDoneOrException in the producer's stop condition: once it is set, no callback will ever consume rows again, so producing more rows is always pointless. Signed-off-by: Fredrik Fornwall <fredrik@fornwall.net>
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This pull request prevents the producer thread in AsyncResultSetImpl from spinning indefinitely when a callback throws an exception while the buffer is full, by checking cursorReturnedDoneOrException in the loop. It also adds a unit test to verify this behavior. The review feedback points out a potential thread leak in the new test because the created ExecutorService is not shut down, and suggests wrapping the test execution in a try-finally block to ensure proper resource cleanup.
Signed-off-by: Fredrik Fornwall <fredrik@fornwall.net>
Signed-off-by: Fredrik Fornwall <fredrik@fornwall.net>
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Check
cursorReturnedDoneOrExceptionwhen deciding if rows shouldcontinue to be produced in
AsyncResultSetImpl, to avoid busy-spinningforever if a user-supplied
ReadyCallbackthrew an exception while therow buffer was full.