Could you rerun the test with a recent JDK 8 build? -- Chris
On Oct 10, 2012, at 3:02 PM, Ashwin Jayaprakash <ashwin.jayaprak...@gmail.com> wrote: > Hi, I was looking at the Java 7 InvokeDynamic/MethodHandle feature set and I > was curious to know how it performed compared to good old Reflection. > > I had refrained from posting this question for some time but I couldn't wait > any longer after I saw a reference to this bug fix > http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7023639 (Bug ID: 7023639 > JSR 292 method handle invocation needs a fast path for compiled code) on this > forum. I suppose this change will go into the Oracle JDK sometime later. > > I still went ahead with Oracle JDK 7u7 and ran a simple test using Google > Caliper (http://code.google.com/p/caliper/) on a Win 7, 64bit, 1 cpu x 2 core > x 4 HT, i7 920 laptop. > > Q1: MethodHandle still seems slower than Reflection. Will that change > sometime in the future? > > Q2: Also, am I using MethodHandle the right way in the code > Temp::timeHandle(int) below? > > Test results: > 0% Scenario{vm=java, trial=0, benchmark=Reflect, serverMode=-server, > memoryMin=-Xmx96M, memoryMax=-Xmx96M} 16.76 ns; ?=0.18 ns @ 10 trials > 20% Scenario{vm=java, trial=0, benchmark=Handle, serverMode=-server, > memoryMin=-Xmx96M, memoryMax=-Xmx96M} 21.98 ns; ?=0.57 ns @ 10 trials > 40% Scenario{vm=java, trial=0, benchmark=Direct, serverMode=-server, > memoryMin=-Xmx96M, memoryMax=-Xmx96M} 4.93 ns; ?=0.06 ns @ 10 trials > 60% Scenario{vm=java, trial=0, benchmark=Iface, serverMode=-server, > memoryMin=-Xmx96M, memoryMax=-Xmx96M} 4.94 ns; ?=0.30 ns @ 10 trials > 80% Scenario{vm=java, trial=0, benchmark=Static, serverMode=-server, > memoryMin=-Xmx96M, memoryMax=-Xmx96M} 4.88 ns; ?=0.03 ns @ 3 trials > > benchmark ns linear runtime > Reflect 16.76 ====================== > Handle 21.98 ============================== > Direct 4.93 ====== > Iface 4.94 ====== > Static 4.88 ====== > > vm: java > trial: 0 > serverMode: -server > memoryMin: -Xmx96M > memoryMax: -Xmx96M > > > Test code: > public class Temp extends SimpleBenchmark { > public static void main(String[] args) throws Exception { > Runner.main(Temp.class, args); > } > > public void timeReflect(int reps) throws Exception { > Method m = K.class.getMethod("exec", Object.class); > > K k = new K(); > > for (int i = 0; i < reps; i++) { > m.invoke(k, i); > } > } > > public void timeHandle(int reps) throws Throwable { > MethodHandle mh = MethodHandles.lookup().findVirtual(K.class, "exec", > MethodType.methodType(void.class, Object.class)); > > K k = new K(); > > for (int i = 0; i < reps; i++) { > mh.invokeExact(k, (Object) i); > } > } > > public void timeDirect(int reps) throws Exception { > Method m = K.class.getMethod("exec", Object.class); > > K k = new K(); > > for (int i = 0; i < reps; i++) { > k.exec(i); > } > } > > public void timeIface(int reps) throws Exception { > M m = new K(); > > for (int i = 0; i < reps; i++) { > m.exec(i); > } > } > > public void timeStatic(int reps) throws Exception { > for (int i = 0; i < reps; i++) { > K.execS(i); > } > } > } > > public class K implements M { > static long s = 0; > > long l = 0; > > @Override > public void exec(Object o) { > l += o.hashCode(); > } > > public static void execS(Object o) { > s += o.hashCode(); > } > } > > public interface M { > void exec(Object o); > } > > Thanks, > Ashwin (http://www.ashwinjayaprakash.com). > _______________________________________________ > mlvm-dev mailing list > mlvm-dev@openjdk.java.net > http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev
_______________________________________________ mlvm-dev mailing list mlvm-dev@openjdk.java.net http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev
