VMS Help  —  RMU72  Optimize  Command Qualifiers, Recovery Method
    Recovery_Method=Sequential
    Recovery_Method=Scatter

    Specifies how .aij records are to be ordered. You can specify one
    of two possible order types:

    o  Sequential-.aij records are ordered by physical dbkey in an
       area:page:line sequence. This order type is the default.

    o  Scatter-.aij records are ordered by a sort key of
       page:area:line (page number, area number, and line number).
       This order can allow the RMU Recover command to perform more
       effective I/O prefetching and writing to multiple storage
       areas simultaneously, typically where storage areas of the
       database are distributed among multiple disk devices.

    Scatter ordering allows more disk devices to be active during
    the recovery process. This helps reduce idle CPU time and allows
    the recovery to complete in less time. However, because database
    configurations vary widely, Oracle recommends that you perform
    tests with both Scatter and Sequential ordering of the optimized
    after-image journals to determine which method produces the best
    results for your system.
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