-XX:-PrintCompilation logging method

Question

When the JVM logs the compilation/decompilation of the class of my program, does it log just before starting the compilation/decompilation or just after it has finished to compile/decompile?

I use -XX:+PrintCompilation for asking JVM to log.

Thanks,

Romain

Answer 1

According to HotSpot sources PrintCompilation prints a line just before starting the compilation of a method (see CompileBroker::invoke_compiler_on_method).

To issue additional compiler info after the compilation is finished, use

-XX:+UnlockDiagnosticVMOptions -XX:+PrintCompilation2

and/or

-XX:+UnlockDiagnosticVMOptions -XX:+TraceNMethodInstalls