1  –  APF start: success field

    The number of times a APF-initiated buffer fetch attempt was
    successful in fetching the buffer. This is possible only if an EX
    lock can be obtained for the whole buffer. A successful APF fetch
    may actually issue an asynchronous read or simply ensure that a
    buffer that was already in the buffer pool now moves to the front
    of the LRU queue. In the latter case, the buffer then becomes
    least likely to be removed from the buffer pool.

2  –  _________:_failure_field_

    The number of times a APF-initiated buffer fetch attempt failed
    due to locking conflicts. If an EX lock cannot be obtained on the
    whole buffer, then the fetch attempt will fail.

3  –  APF I O: utilized field

    If a buffer is fetched by APF, it is marked APF_FETCHED. If the
    buffer is accessed again, then this statistic is incremented
    to indicate that prefetching the buffer by APF was worthwhile.
    The statistic is incremented only the first time the buffer is
    accessed.

4  –  _______:_wasted_field_

    If a APF-fetched buffer is removed from the buffer pool without
    being accessed, then this statistic is incremented to indicate
    that fetching the buffer was not worthwhile.

5  –  DAPF start:success field

    The number of times a DAPF-initiated buffer fetch attempt was
    successful in fetching the buffer. This is possible only if an
    EX lock can be obtained for the whole buffer. A successful DAPF
    fetch may actually issue an asynchronous read or simply ensure
    that a buffer that was already in the buffer pool now moves to
    the front of the LRU queue. In the latter case, the buffer then
    becomes least likely to be removed from the buffer pool.

6  –  __________:failure_field__

    The number of times a DAPF-initiated buffer fetch attempt failed
    due to locking conflicts. If an EX lock cannot be obtained on the
    whole buffer, then the fetch attempt will fail.

7  –  DAPF I O: utilized field

    If a buffer is fetched by DAPF, it is marked DAPF_FETCHED. If
    the buffer is accessed again, then this statistic is incremented
    to indicate that prefetching the buffer by DAPF was worthwhile.
    The statistic is incremented only the first time the buffer is
    accessed.

8  –  ________:_wasted_field_

    If a DAPF-fetched buffer is removed from the buffer pool without
    being accessed, then this statistic is incremented to indicate
    that fetching the buffer was not worthwhile.