Reputation: 939
I have simple hello world program, and set -XX:TieredStopAtLevel=[0 to 4]
. I understand the basic difference how it uses either interpreter or C1 or C2 or both C1 and C2 to compile code.
I'd like to know real benchmark details to know compile time, and others details if i use different numbers.
Upvotes: 1
Views: 1421
Reputation: 98284
To benchmark JIT compilers, use -Xcomp
to force compilation of all executed methods, and check CompilationMXBean.getTotalCompilationTime
to find the total time spent in JIT compilation.
import java.lang.management.ManagementFactory;
public class CompilationTime {
public static void main(String[] args) throws Exception {
System.out.println(ManagementFactory.getCompilationMXBean().getTotalCompilationTime());
}
}
C1
$ java -Xcomp -XX:TieredStopAtLevel=1 CompilationTime
162 // milliseconds
C2
$ java -Xcomp -XX:-TieredCompilation CompilationTime
1129 // milliseconds
Upvotes: 6