Loader_Synchronization[=Fixed]

    Allows you to preload tapes and preserve tape order to minimize
    the need for operator support. When you specify the Loader_
    Synchronization qualifier and specify multiple tape drives,
    the backup operation writes to the first set of tape volumes
    concurrently then waits until each tape in the set is finished
    before assigning the next set of tape volumes. This ensures
    that the tape order can be preserved in the event that a restore
    operation from these tapes becomes necessary.

    One disadvantage with using the Loader_Synchronization qualifier
    with the Label qualifier is that because not all tape threads
    back up equal volumes of data, some threads may not need a
    subsequent tape to back up the assigned volume of data. In order
    to preserve the tape order, operator intervention may be needed
    to load the tapes in stages as backup threads become inactive.
    Use the keyword Fixed to force the assignment of tape labels to
    the drives regardless of how many tapes each drive actually uses.

    The Loader_Synchronization qualifier does result in reduced
    performance. For maximum performance, no drive should remain
    idle, and the next identified volume should be placed on the
    first drive that becomes idle. However, because the order in
    which the drives become idle depends on many uncontrollable
    factors and cannot be predetermined, without the Loader_
    Synchronization qualifier, the drives cannot be preloaded with
    tapes. (If you do not want to relabel tapes, you might find that
    the Accept_Label qualifier is a good alternative to using the
    Loader_Synchronization qualifier. See the description of the
    Accept_Label qualifier for details.)

    Because the cost of using the Loader_Synchronization qualifier is
    dependent on the hardware configuration and the system load, the
    cost is unpredictable. A 5% to 20% additional elapsed time for
    the operation is typical. You must determine whether the benefit
    of a lower level of operator support compensates for the loss of
    performance. The Loader_Synchronization qualifier is most useful
    for large backup operations.

    See the Oracle Rdb Guide to Database Maintenance for more
    information on using the Loader_Synchronization qualifier,
    including information on when this qualifier might lead to
    unexpected results, and details on how this qualifier interacts
    with other RMU Backup command qualifiers.

    For very large backup operations requiring many tape volumes,
    managing the physical marking of tape volumes can be difficult.
    In such a case, you might consider using a library or archiving
    to automatically manage tape labeling for you.