Profiling an application in standalone mode on AS/400

Prerequisites:

• Profiling an application in standalone mode

To profile an application in standalone mode on AS/400, there are a few important points that need to be considered:

1. In order to enable method entry or method exit events for JIT-ed methods, use the 'os400.enbpfrcol=1' property. For example, to profile the MyApp application,

           java -XrunMyJvmpiPrf -Dos400.enbpfrcol=1 MyApp
       

   .

2. Direct Execution (DE) optimization level 40 does not include the instructions needed to enable method entry/exit events. Since the JDK jar files are shipped with DE optimization level 40, method entry/exit events will not be generated for JDK classes unless the JVM runs in pure JIT mode or Interpreted mode. Pure JIT mode is enabled using the 'java.compiler=jitc' property. In order to see all method entry/exit events do the following:

           java -XrunMyJvmpiPrf -Dos400.enbpfrcol=1 -Djava.compiler=jitc MyApp
       

Related tasks
Profiling an application
Profiling an application in standalone mode

Related references
Limitations when profiling an application on AS/400