1  –  FIB update attempt field

    This field displays the number of times the fast incremental
    backup (FIB) operation was attempted. The attempt does not always
    result in the SPAM page being updated.

2  –  FIB map updated field

    This field displays the number of times the FIB map, a per-
    process data structure, was updated. This data structure
    indicates when each process no longer needs to update a
    particular SPAM page.

3  –  SPAM page updated field

    This field displays the number of times a SPAM page was
    immediately modified to indicate that one or more pages in the
    SPAM interval have been modified since the last incremental
    backup. Each SPAM page update results in one synchronous read
    I/O and one synchronous write I/O operation.

4  –  SPAM updt deferred field

    This field displays the number of times a SPAM page did not need
    to be immediately modified, but might have to be modified at a
    later time. In most cases, this statistic closely follows the FIB
    update attempt statistic.