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A barrier is a synchronization object which can be used to synchronize a group of sessions to a specific rendezvous by calling wait(). When wait() is called, any session of the user may call signal(), allowing all sessions being held by wait() to proceed.
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Barriers can optionally be created with a limit so that once a set number of sessions have called wait() that all "waiters" are then allowed to proceed.
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The session that creates the barrier via create_barrier() is not allowed to call either wait() or wait_until().
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A barrier is a synchronization object which can be used to synchronize
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a group of sessions to a specific rendezvous by calling wait(). When
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wait() is called, any session of the user may call signal(), allowing
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all sessions being held by wait() to proceed.
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Barriers can optionally be created with a limit so that once a set
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number of sessions have called wait() that all "waiters" are then
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The session that creates the barrier via create_barrier() is not
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allowed to call either wait() or wait_until().
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The scope of barriers is to the given username.
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Beyond waiters, you can also create observers by using the wait_until() function. Observers are released not only when signal() or release_barrier() is called, but also when their definitive predicate happens. You can use wait_until() to have a session wait for a certain number of waiters to occur, and then do some body of work before the waiters() are signaled to continue.
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Beyond waiters, you can also create observers by using the
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wait_until() function. Observers are released not only when signal()
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or release_barrier() is called, but also when their definitive
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predicate happens. You can use wait_until() to have a session wait for
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a certain number of waiters to occur, and then do some body of work
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before the waiters() are signaled to continue.
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All waiters and observers are released if release_barrier() is called by the session which created the barrier. Also, if the session that created the barrier disconnects, all waiters and observers are notified.
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All waiters and observers are released if release_barrier() is called
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by the session which created the barrier. Also, if the session that
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created the barrier disconnects, all waiters and observers are
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Information on all barriers can be found in the DATA_DICTIONARY.USER_BARRIERS table.