Duration Performance Measurements - HP 64782 User Manual

Duration Performance Measurements

Duration measurements provide a best-case/worst-case characterization of
code execution time. These measurements record execution times that fall
within a set of specified time ranges. The analyzer trace command is set up
to store only the entry and exit states of the module to be measured (for
example, a C function or Pascal procedure). The SPMT provides two types of
duration measurements: module duration, and module usage.
Module duration measurements record how much time it takes to execute a
particular code segment (for example, a function in the source file).
Module usage shows how much of the execution time is spent outside of the
module (from exit to entry). This measurement gives an indication of how
often the module is being used.
When using the SPMT to perform duration measurements, there should be
only two addresses stored in the trace memory: the entry address, and the
exit address. Recursion can place several entry addresses before the first
exit address, and/or several exit addresses before the first entry address.
Duration measurements are made between the last entry address in a series
of entry addresses, and the last exit address in a series of exit addresses (see
the figure below). All of the entry and exit addresses which precede these
last addresses are assumed to be unused prefetches, and are ignored during
time measurements.
START - assumed prefetch
START - assumed prefetch
START - assumed prefetch
START - last ENTRY address -
END - assumed prefetch
END - assumed prefetch
END - assumed prefetch
END - last EXIT address -
START - assumed prefetch
START - assumed prefetch
START - assumed prefetch
START - last ENTRY address -
END - assumed prefetch
END - assumed prefetch
Measure duration
Measure duration
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