To help you tune application performance, the runtime includes an execution profiling facility. This built-in facility is activated when a properly prepared program is executed with the -p flag, prompting the runtime to collect information about I/O operations and CALLs, and to install a timer to track the amount of time spent in different parts of the code. All of this information is placed into an output file called acumon#.xml. (The # is an automatically incremented number, starting at 1, appended to the filename to ensure that the profile data is not accidentally overwritten by another execution of the profiler.)
The raw data in acumon#.xml can be processed by the acuprof utility to create a text-based performance report, acumon.rpt. In all environments, the report summarizes the amount of processor time used by each program in an application and each paragraph in a program, as well as detailing the file I/O operations performed by each program. When the acumon#.xml file is created by a UNIX/Linux runtime, the final report also contains information about the amount of user time spent in each program and paragraph.