StorageTek 312564001 Manuale Utente
DB2 Manager User Guide
65
StorageTek
Proprietary
4. Termination of request processing by the reader or writer task in the
control region.
Analysis of timestamp intervals will provide timings for the following activities:
• 4 - 1 :
total time for DB2 Manager to process the request.
• 2 - 1:
time spent in control region scheduler queue.
• 3 - 2:
time spent in reader or writer task queue.
• 4 - 3:
time taken to retrieve object from tape or disk and locate
migrated row (reader tasks) or to add migrated row to
Archive Manager object (writer tasks).
Careful analysis of this information will assist in identifying possible
performance problems during object retrieval processing.
performance problems during object retrieval processing.
The following sections describe the individual components that constitute the
DB2 Manager SMF record.
DB2 Manager SMF record.
SMF header section
Each SMF record will have a standard SMF header section of length 18
bytes.
bytes.
Offset Length Format Description
0
2
bin
Record length. This is the length of
the entire SMF record, including this
field.
the entire SMF record, including this
field.
2
2
bin
Segment descriptor - binary zeroes.
4
1
bin
System indicator - binary zeroes.
5
1
bin
Record type (equal to the value of the
SMF record identifier specified
defined for the database being
processed).
SMF record identifier specified
defined for the database being
processed).
6
4
bin
Time since midnight, in hundredths of
a second, that the SMF record was
written.
a second, that the SMF record was
written.
10
4
packed
Date record was written, in the format
0cyydddF, where F is the sign.
0cyydddF, where F is the sign.
14
4
char
System identification (from CVT).