IBM Power Systems 775 Manual page 156

Figure 2-18 Xprof source code window
The source code window contains information for source code line number and number of
ticks per line. Each tick represents 0.01 seconds of CPU time that is used and the value of
each line represents the number of ticks that is used by the corresponding line of code. This
information is used to find hot spots of source code and to optimize the applicator.
Using the hpccount command
The hpccount command is a command line tool included in the IBM HPC Toolkit that is used
in the same manner as the time command. Performance counter data is provided to
characterize the performance of the application on POWER7 hardware with the intent of
finding the bottlenecks of performance and looking for opportunities to optimize the target
application code. By using hpccount, you monitor the activity of all POWER7 subsystems,
including the measurements for cache misses at all levels of cache, the number of floating
point instructions that are executed, the number of load instructions that result in TLB misses,
and other measurements that are supported by hardware.
The following format of hpccount is used most often:
hpccount <program>
If you use the hpccount command to measure the performance of your parallel program, you
must invoke hpccount with the following format:
poe hpccount <program>
If you invoke hpccount as hpccount poe <program>, the performance data is shown for the poe
command, not the performance data for your parallel program.
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IBM Power Systems 775 for AIX and Linux HPC Solution