All,

Will start by saying that this is more philosophical than code/pseudo-code. I'm also in the "early stages" of learning threads with Perl. Have written a couple threaded apps for file operations, but now looking to expand that knowledge.

After many hours of searching, reading and trying to establish "an optimal method" - looking for opinion/guidance/suggestion/etc.

  • Suspect Boss/Worker(s) is the correct solution for my paradigm
  • Based on Boss/Worker, the items below expresses "desirable" end-state.
  • Queues via Thread::Queue
    • Boss:
  • Waits for <STDIN>
  • Appends manipulated input to $TXQUEUE->enqueue()
  • Monitor $RXQUEUE and <STDIN> - simultaneously???
  • Sends <STDOUT> while(my $RESULT=$RXQUEUE->dequeue_nb()), until $RXQUEUE is empty. $RESULT is sent "AS-IS"
    • Worker(s):
  • Obtain next queue item from $TXQUEUE->dequeue_nb()
  • Interact with data engines to derive answer
  • Append result(s) to $RXQUEUE->enqueue()
  • Monitor $TXQUEUE
    • Errata:
  • Right now to bridge the gap, there may be as many as 50 instances of this "middleware" between the data engines and the application.
  • Each middleware instance (upon instantiation) creates connections to the data engines, for the life of the process, to avoid connection overhead.
  • Currently using a while(my $INPUT=<STDIN>) - it's simple text artifacts being prefaced by a transaction ID.
  • At the moment, the transaction rate can vary from zero to +/- 50 at any given moment. May go minutes without a transaction or may sustain an average between 30-42 per second for 45-90 seconds.
  • Does not run and exit. Kept open by application, until application is shutdown
  • Most examples seen appear to be something that passes the socket to worker to complete vs. activity to worker and then obtain worker result to provide response -or- appear to run until complete and exit vs. keeping thread(s) idle/monitoring for next transaction(s). (May have missed a superb example out there?)
    • Questions:
  • Have seen a lot of posts about not using Perl library 'X' for pools/etc. For 5.24 (or better) is that still the prevailing perspective? (eg: no better mouse trap)
  • Have seen the use of "usleep", is that the best method for "idling" a worker thread?
  • Is there a way to achieve the benefit of the while loop (avoid CPU cycle consumption while idle), but then issue of providing results to <STDOUT> the moment (or very close to when) they are available?

    • Thanks!

    In reply to Threading with a twist by scorpion7

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