TPDC Manual (G06.24+)

Table Of Contents

Using the Collected Data

Tandem Performance Data Collector (TPDC) Manual—526357-001

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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.