HP Caliper User's Guide

• cpu
For the cpu measurement, you can use this option in conjunction with the
--event-defaults option to control how samples are taken. For more
information, see “Performing CPU Metrics Analysis ” (p. 197).
• cstack
For more information, see Chapter 11 (page 171).
period
Sampling period in seconds or milliseconds or microseconds, measured in
CPU cycles (for cpu) or real time (for cstack). For example:
• -s 1s (1 second)
• -s 100ms (100 milliseconds)
• -s 1000us (1000 microseconds)
For the cpu measurement, the default period is 8 milliseconds. See also
“--cpu-aggregation ” (p. 75).
For the cstack measurement, the default period is 100 milliseconds.
-s rate
The -s rate version of this option is used for all other measurements.
rate
Sampling period: specifically, how many
sampling events should occur between samples.
The smaller the rate, the more chance that HP
Caliper will affect your program's performance
while collecting information.
variation
Sampling period variation: specifically, how
much to vary the number of events between
samples. The variation is the number or
percentage of cpu_counter events that HP
Caliper uses to vary the sampling rate. HP
Caliper adds or subtracts this number from the
interval to vary the sampling frequency.
You can specify the actual number of events by
which to vary the sampling rate, or a percentage
of the count by using a percent symbol (%). For
example: -s CPU_CYCLES,10000,10%
The default value is 5 percent.
cpu_event
Specifies a CPU event to measure. The name is
not case-sensitive. For information about CPU
events you can specify, see “Specifying Which
CPU Events to Measure” (p. 123).
70 HP Caliper Options