System wide central processing unit (CPU) profiling calculates the relative amount of CPU time that is spent in each Java™ method and all system functions in use by your Java program.
Use a Performance Explorer (PEX) definition that traces performance monitor counter overflow (*PMCO) run cycle events. Samples are typically specified in intervals of one millisecond. To collect a valid trace profile, you should run your Java application until it accumulates two to three minutes of CPU time. This should produce over 100,000 samples. The Print Performance Explorer Report (PRTPEXRPT) command produces a histogram of CPU time that is spent across the entire application. This includes every Java method and all system-level activity. The Performance Data Collector (PDC) tool also provides profile information about the programs that run on the iSeries™ server.