Assertion failure in TransactionIndexBucket#allocateTransactionStatus

[Peter Beaman]

Observed in 8-hour stress test run.

Stress2txn [Thread-1154] FAILED [Thread-1154]: java.lang.AssertionError
        at com.persistit.TransactionIndexBucket.allocateTransactionStatus(TransactionIndexBucket.java:177)
        at com.persistit.TransactionIndex.registerTransaction(TransactionIndex.java:560)
        at com.persistit.TransactionIndex.registerTransaction(TransactionIndex.java:527)
        at com.persistit.Transaction.begin(Transaction.java:595)
        at com.persistit.Transaction.run(Transaction.java:979)
        at com.persistit.stress.unit.Stress2txn.executeTest(Stress2txn.java:121)
        at com.persistit.stress.AbstractStressTest.run(AbstractStressTest.java:89)
        at java.lang.Thread.run(Thread.java:662)

The likely culprit is that commitStatus() briefly locks and then unlocks a TransactionStatus and this assert is caused by a race.

Note that this bug has exactly the same title as

https://bugs.launchpad.net/bugs/932097

but is caused by an entirely different mechanism. The bug is benign in that the assert is on a transient condition that will be rectified shortly. The solution will be to test the isLocked() condition, and if set briefly tryLock to wait for the thread performing commitStatus to finish.