HP Pascal/HP-UX Release Notes Version A.10.08

24 Chapter 1
New and Changed Features
Profile-Based Optimization (PBO)
Maintaining Multiple Profile Data Files
By default, PBO logs the profile statistics in a file called flow.data. You
can specify another name with the +df compile-line option.
The name of the executable file used during profiling is the name under
which the profile data is stored in the database file. If you specify a
different executable output file name during the optimization phase, you
need to use the +pgm option to specify the program name used during
profiling. The following steps and example demonstrate the use of +df
and +pgm.
1. Rename flow.data after performing the data collection step
described previously:
mv flow.data sample.data
2. Perform PBO on this application by re-linking the program as follows:
pc -o sample.opt -O +P +pgm sample.inst +df sample.data
sample.o
The default value for the +df compile-line option is flow.data. The
+df option is used because the profile data file for the program has
been moved from flow.data to sample.data.
The +pgm option is used because the instrumented program file is
sample.inst, and the optimized program file is sample.opt.
You can also use the FLOW_DATA environment variable to specify a
different path name for the profile database file. Note, however, that
the +df compile-line option takes precedence over the FLOW_DATA
environment variable. For more information about the profile
database and the FLOW_DATA environment variable, see HP-UX
Linker and Libraries Online User Guide.