UIMA
  1. UIMA
  2. UIMA-1800

UIMA AS should block msg submitter thread if a thread pool is empty

    Details

    • Type: Bug Bug
    • Status: Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: 2.3AS
    • Fix Version/s: 2.3.1AS
    • Component/s: Async Scaleout
    • Labels:
      None

      Description

      If a queue scaleout factor > 1, the UIMA AS creates a thread pool and a managing Executor object. The threads in a pool are used to process incoming messages. A submitter thread receives a jms message via a callback from Spring and delivers it to the Executor for processing in one of the threads from the pool. If a thread pool is empty, the Executor policy is to use the submitter thread to process the message. Since there is a single submitter thread (per queue) this policy slows down the submitter thread and prevents it from delivering messages for processing by other threads.

      Change the code to prevent the submitter thread from doing processing. Instead, block the submitter thread if the thread pool becomes empty. As soon as a thread becomes available, the submitter thread should deliver a message and wait for a callback from Spring.

        Activity

        Hide
        Jerry Cwiklik added a comment -

        Modified the UIMA AS listener code to use new UimaBlockingExecutor which uses a semaphore with multiple permits to throttle message processing. A submitter thread first requests a free permit from a semaphore and if one is available it is allowed to submit a message to a thread pool for processing. If there are no permits available ( meaning all threads in a pool are busy processing previous messages), the submitter thread blocks. It is unblocked once a new thread becomes available

        Show
        Jerry Cwiklik added a comment - Modified the UIMA AS listener code to use new UimaBlockingExecutor which uses a semaphore with multiple permits to throttle message processing. A submitter thread first requests a free permit from a semaphore and if one is available it is allowed to submit a message to a thread pool for processing. If there are no permits available ( meaning all threads in a pool are busy processing previous messages), the submitter thread blocks. It is unblocked once a new thread becomes available
        Hide
        Jerry Cwiklik added a comment - - edited

        Revert code that handles internal messaging (to/from colocated delegate) to previous version that is not using BlockingThreadExecutor. Specifically, revert VMTransport and UimaVmMessageDispatcher. The BlockingExecutor should still be used to process reply messages from remotes. For colocated components dont require a samphore for submitting messages to a queue.

        Show
        Jerry Cwiklik added a comment - - edited Revert code that handles internal messaging (to/from colocated delegate) to previous version that is not using BlockingThreadExecutor. Specifically, revert VMTransport and UimaVmMessageDispatcher. The BlockingExecutor should still be used to process reply messages from remotes. For colocated components dont require a samphore for submitting messages to a queue.

          People

          • Assignee:
            Jerry Cwiklik
            Reporter:
            Jerry Cwiklik
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            Dates

            • Created:
              Updated:
              Resolved:

              Development