TPDC Manual (H06.03+, J06.03+)

Using the Collected Data
Tandem Performance Data Collector (TPDC) Manual—529899-002
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File Name Spaces
value of 10 is the opener of this DISCOPEN. Varying degrees of linking exist between
entities. PROCESS is linked to ten entities.
File Name Spaces
To conserve space, all file names are projected out to three entities:
•
FLABNAME
•
LDEVNAME
•
TPDCNAME
The linkage to FLABNAME-LINK is the replacement. The FLABNAME entity is an
artificial construct, consisting of linkages:
•
Volume linkage LDEVNAME-LINK
•
Subvolume linkage TPDCNAME-LINK
•
Filename linkage TPDCNAME-LINK
This approach results in a space reduction of at least 65% to store the names.
Typically, the larger or longer the measurement, the greater the percentage of space
reduction.
ASCII Name Spaces
ASCII name spaces were projected out of all the ASCII name entities into separate
entities that have duplicates removed and are in sorted order. This approach
conserves space and provides more information about the use of names.
TIME Fields
To conserve space, all times are converted from microseconds to millisecond offsets
and durations. In the original Measure entities, the FROM-TIME and TO-TIME are held
in quadruple word microsecond values (16 bytes). In TPDC, the time for entities is held
in the TIMETPL entity and linked to via the TIMETPL-LINK field.
In the TIMETPL entity, the millisecond offset and durations are held. The TIME entity
has two base microsecond times (GMT and LCT). The actual start time is calculated by
adding the appropriate millisecond offset from TIMETPL to either base time. The end
time is calculated by adding both the millisecond time offset and duration to either base
time.
This mechanism provides minimal storage and multiple time zone analysis using a
worldwide time standard (GMT). The maximum loss of accuracy is one millisecond.