This screen shows transaction and checkpoint activity. Statistics
    are displayed for all processes on the node for a particular
    database. The total number of checkpoints, with a breakdown
    of the reasons for checkpointing, is displayed. The sum of all
    checkpoint intervals is also displayed, using three different
    metrics. You can use this information to compute the average
    interval between checkpoints, allowing you to decide if a
    checkpointing interval should be adjusted, and by how much.

    Some of the columns provided by the Checkpoint Statistics
    screen measure events on a per second or per transaction basis.
    These columns are useful for measuring frequently occurring
    events such as I/O operations. Because checkpointing typically
    occurs at a slower rate, you will find the most meaningful
    checkpointing information in the total count column of the
    Checkpoint Statistics screen. Oracle Corporation recommends that
    you refer to this column when you use checkpoint statistics to
    determine optimal checkpoint intervals.