Java Benchmarks of lambdas

LambdaBenchmark.java

/*
 * Benchmarks of Java 8
 */

package benchmarks;

import java.util.concurrent.TimeUnit;
import java.util.function.Supplier;

import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.GenerateMicroBenchmark;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.State;

@BenchmarkMode(Mode.SampleTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Fork(value = 1, jvmArgsAppend = {
		"-server",
		"-disablesystemassertions",
		"-Xms16m",
		"-Xmx16m",
		"-XX:+PrintGC",
		"-XX:+PrintGCTimeStamps",
		"-Xloggc:target/gc.log"})
@State(Scope.Thread)
public class LambdaBenchmark {
	private static final Integer CACHED = Integer.valueOf(0);
	private static final int LOOP_TIME = 1000000;

	private int result;

	@GenerateMicroBenchmark
	public void side_effect_free__baseline() {
		call();
	}

	@GenerateMicroBenchmark
	public void side_effect_free__lambda() {
		lazy(() -> call());
	}

	@GenerateMicroBenchmark
	public void side_effect_free__methodReference() {
		lazy(this::call);
	}

	@GenerateMicroBenchmark
	public void side_effect__baseline() {
		int a = call();
		result = a + 5554478;
	}

	@GenerateMicroBenchmark
	public void side_effect__lambda() {
		int a = lazy(() -> call());
		result = a + 5554478;
	}

	@GenerateMicroBenchmark
	public void side_effect__methodReference() {
		int a = lazy(this::call);
		result = a + 5554478;
	}

	@GenerateMicroBenchmark
	public void extensiveLoop__baseline() {
		int a;
		for (int i = 0; i < LOOP_TIME; i++) {
			a = call();
			result = a + i;
		}
	}

	@GenerateMicroBenchmark
	public void extensiveLoop__lambda() {
		int a;
		for (int i = 0; i < LOOP_TIME; i++) {
			a = lazy(() -> call());
			result = a + i;
		}
	}

	@GenerateMicroBenchmark
	public void extensiveLoop__methodReference() {
		int a;
		for (int i = 0; i < LOOP_TIME; i++) {
			a = lazy(this::call);
			result = a + i;
		}
	}

	private Integer call() {
		return CACHED;
	}

	private int lazy(Supplier<Integer> supp) {
		return supp.get();
	}

}

LambdaMemory.java

package benchmarks;

import java.util.function.Supplier;

public class LambdaMemory {
	static final Object lock = new Object();
	static long threshold = 0;
	final Integer boxedValue = 0;

	static void caseOne(LambdaMemory lambdaTest) {
		for (int i = 0; i <= threshold; i++) {
			lambdaTest.call();
		}
	}

	static void caseTwo(LambdaMemory lambdaTest) {
		for (int i = 0; i <= threshold; i++) {
			lazyCall(() -> lambdaTest.call());
		}
	}

	static void caseThree(LambdaMemory lambdaTest) {
		for (int i = 0; i <= threshold; i++) {
			lazyCall(lambdaTest::call);
		}
	}

	static int lazyCall(Supplier<Integer> function) {
		return function.get();
	}

	public static void main(String[] args) throws Exception {
		System.out.print("press to start");
		System.in.read();
		System.out.println("Starting ..");
		LambdaMemory lambdaTest = new LambdaMemory();
		threshold = Long.parseLong(args[1]);
		for (int i = 0; i <= threshold; i++) {
			switch (Integer.parseInt(args[0])) {
				case 1:
					caseOne(lambdaTest);
					break;
				case 2:
					caseTwo(lambdaTest);
					break;
				case 3:
					caseThree(lambdaTest);
					break;
			}
		}
		System.out.println("Ctrl+C to finish ..");
		synchronized (lock) {
			lock.wait();
		}
	}

	public Integer call() {
		return boxedValue;
	}

}

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>ch.pterrettaz.playground</groupId>
	<artifactId>benchmarks</artifactId>
	<version>1.0-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>Auto-generated JMH benchmark</name>

	<dependencies>
		<dependency>
			<groupId>org.openjdk.jmh</groupId>
			<artifactId>jmh-core</artifactId>
			<version>0.5.6</version>
		</dependency>
		<dependency>
			<groupId>org.openjdk.jmh</groupId>
			<artifactId>jmh-generator-annprocess</artifactId>
			<version>0.5.6</version>
			<scope>provided</scope>
		</dependency>
	</dependencies>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
	</properties>

	<build>
		<sourceDirectory>${basedir}</sourceDirectory>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.0</version>
				<configuration>
					<compilerVersion>1.8</compilerVersion>
					<source>1.8</source>
					<target>1.8</target>
				</configuration>
			</plugin>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-shade-plugin</artifactId>
				<version>2.0</version>
				<executions>
					<execution>
						<phase>package</phase>
						<goals>
							<goal>shade</goal>
						</goals>
						<configuration>
							<finalName>microbenchmarks</finalName>
							<transformers>
								<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
									<mainClass>org.openjdk.jmh.Main</mainClass>
								</transformer>
							</transformers>
						</configuration>
					</execution>
				</executions>
			</plugin>
		</plugins>
	</build>
</project>