This field displays the sum of the intervals between time in
    seconds checkpoints for all processes. For example, if Process
    1 checkpoints after 500 seconds, the time in seconds category is
    incremented by 500. If Process 2 checkpoints after 600 seconds,
    the time in seconds category is incremented by an additional 600.
    Statistics for the other two interval categories are displayed in
    the "interval: AIJ blks" and "interval: tx count" fields.

    If CHECKPOINT TIMED EVERY 600 SECONDS is specified with the
    SQL ALTER DATABASE statement, each process checkpoints every
    10 minutes.

    Keep in mind that checkpointing influences recovery time. The
    main reason to consult checkpoint statistics is to find the
    average interval per checkpoint. You can use the information in
    the total count column to compute this average. For each category
    of checkpoint reason, use the average interval per checkpoint to
    help you decide if a checkpointing interval should be adjusted,
    and by how much.

    If most of the checkpoints for a database are triggered by a
    particular checkpoint limit, that limit may be set too high,
    or the other two limits may be set too low. You can determine
    the average interval per checkpoint for each type of checkpoint
    limit. After you have this information, you can reset the limits
    so that each type of checkpoint limit triggers approximately the
    same number of checkpoints, which results in optimal performance.

    To compute the average time interval, divide the total count for
    seconds interval by the total number of checkpoints. If the total
    count for the seconds field is 59,300 and the total number of
    checkpoints is 100, the average number of seconds between each
    time-triggered checkpoint is 593.

          59,300 / 100 = 593

    The help for the "interval: AIJ blks" field explains how to
    determine the average interval for .aij file growth checkpoints.

    The help for the "interval: tx count" field explains how to
    determine the average interval for transaction checkpoints.