Thread Pool in JRT

Hi All,
1) the first question is what is the recommended way to allocate thread poll in rt system??
2) what is the best way to do:
-if my mission take a long time can i just suspend the thread and than resume it again (is it possible at all??)
or the other option is to return it to the pool and get it again and again.
im asking the second question from the view of performance and low latency .
i assumed that each time i return the thread to the pool and than active it again it will "cost" cpu time.
hope my question is clear enough.
TIA
Gabi

Hi Gabi,
I'm not completely clear on your questions. You can create a thread pool in a RT system the same basic way as in non-RT but you need to deal with priorities correctly. One way to do this would be to have the pool threads run at maximum priority normally and then drop to the actual priority of a submitted work task. Another model is to split the pool into groups based on priority, so effectively there is a work queue per priority-level and a group of threads to service each pool. This second model is used in the Real-time CORBA "lanes" approach. Designing an effective thread pool is a non-trivial task (take a look at the java.util.concurrent Thread PoolExecutor) and dealing with RT priorities and RT latency issues makes it even more complex.
Alternatively rather than use an explicit thread pool consider whether you can convert the design to one using AsyncEvents and AsyncEventHandlers.
Question 2 I don't really understand. Pool threads typically block on a queue waiting for work tasks to appear. But you can also have a non-terminating task that effectively picks up its own work from elsewhere - eg a task that reads from a socket to get the next "job" to process. Any interaction between threads is going to cost CPU time, whether a pool is involved or not, but yes there will be overhead associated with a pool, just as there is starting and terminating a thread, or performing any kind of thread coordination/synchronization.
Regards,
David Holmes

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         Rejected: 1
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    Exiting run: 9
    Exiting run: 8
    </pre>

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    2: 1
    3: 2
    4: 3
    5: 4
    6: 5
    7: 6
    8: 7
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    10: 9
    11: 10
    12: 10
    13: 10
    14: 10
    15: 10
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