• Bug
  • Status: Open
  • 2 Major
  • Resolution:
  • Byte Code Transform
  • cdennis
  • Reporter: teck
  • May 12, 2009
  • 0
  • Watchers: 0
  • October 11, 2011


There is no common lock (with respect to put/offer) when an LBQ is empty. It is possible to get an invalid NoSuchElementException from remove() (which is based on poll()) in this case (see DEV-2797). The AtomicInteger inside of LBQ is relevant to behavior of LBQ in this regard but this counter is not clustered – as such you can get back null from poll() since you can race with receiving a broadcast of the put/offer.

The caution here is that naive clustering of that internal counter will probably greater affect (negatively) the effectiev concurrency of an LBQ in the cluster.


Fiona OShea 2010-10-28

Can we add the workaround to comments?