This screen provides summary record access information for
all processes activated to collect global statistics using the
Process Monitoring facility.
The processes displayed on this screen have previously activated
their global statistics collection. Process global statistic
collection can be either implicitly activated by the database
monitor, or explicitly activated by the RMU Show Statistic
utility.
This screen provides the following information:
o Process.ID
The process ID for the current process, assigned by the
operating system, and the stream ID, assigned by the database.
If "G" is appended to the process ID, the process had been
activated for global statistics collection; this is the normal
case. Server processes will be designated with the "s" tag.
o RecFetched
This field gives the number of records fetched, including
snapshot records. This field does not include records
retrieved from a temporary table.
Note that this value may be more than the actual number of
records returned by a query. The reason is that queries may
fetch records during the search phase, and then refetch the
selected records so that they may be returned to the user.
Also, for uniform format storage areas, a sequential scan
needs to fetch the "next" record on each page of the clump,
even if there are no records on that page. In addition, every
page in a uniform format storage area incurs an extra fetch to
verify that there are no more records residing on that page.
o Rec.Marked
This field gives the number of records marked. A record is
marked when it is modified or it is erased, but not when it
is stored. This field does not include records modified in a
temporary table.
o Rec.Stored
This field gives the number of records stored in the database.
This field does not include records stored in temporary
tables.
o Pag.Checkd
This field indicates the number of pages checked in order
to store a record. Ideally, very few candidate pages need to
be checked when storing a record. However in certain cases,
depending on record size, access method, locked space on a
page, and SPAM thresholds, storing a record requires a number
of page fetches.
o PagDiscard
This field identifies the number of pages checked but
discarded because the actual free space on that page did not
meet the physical requirements needed to store a new record.
o Rec.Erased
This field gives the number of records erased from the
database. This field does not include records erased from
temporary tables.