|Perl: the Markov chain saw|
Re^8: Thread terminating abnormally COND_SIGNAL(6)by rmahin (Scribe)
|on Jul 18, 2013 at 01:44 UTC||Need Help??|
I really apologize, i dont think I'm being completely clear.
Hm. But, queues DO preserve order. That's kind of their raison d'Ítre. (And they also 'close up the gaps' automatically!)
Generally speaking, yes they do. However in our case I really think there would be potential for things to be executed out of order using a standard queue, but not because of any fault in the queueing mechanism. Because using a typical queue, would mean we query the database before processing each node to see if resources are available-- this would immediately free up any resources and allow jobs to execute even if there were preceeding nodes that were refused and requeued. Do you follow?
If instead, (in your scenario above), you queued two items for each of your 3 users;
Again I apologize, they are being treated as individual items. So take the example again.
Using an actual queue the process would be the following
Now obviously, there would be ways to avoid that issue, if for instance the jobs were not incrementing their session counter off in other threads somewhere, but this would just require a rather larger to change to existing framework.
That said; I'm still not clear on why you need the shared %nodes hash, when the results from the jobs are returned to the main thread via the $Qresults?
In the actual program results are not returned to the main thread. The main thread just listens for client connection and passes the file descriptor to client threads. Results are sent back to the user, or discarded if the job was executed in the background. The %nodes hash was just to pass information back to the jobnode in the originating thread. My understanding was that when you enqueue something into the Thread::Queue, you get shared_clone of that object and thus cannot make direct modifications to the object. The hash is simply the means for returning information to the jobNode in the originating thread. Hence the
The process is:
If there is another way to get the job number from the job queue I am all ears. I thought the shared hash was a good implementation for what i needed but yeah if theres a better way to do it, happy to listen and try it out.
Thanks again for your responses!