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package org.openjdk.bench.java.net;

import jdk.internal.event.SocketReadEvent;
import jdk.internal.event.SocketWriteEvent;
import org.openjdk.jmh.annotations.*;
import org.openjdk.jmh.runner.Runner;
import org.openjdk.jmh.runner.options.Options;
import org.openjdk.jmh.runner.options.OptionsBuilder;

import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.util.concurrent.TimeUnit;

/**
 * Test the overhead of the handling jfr events SocketReadEvent and
 * SocketWriteEvent without the latencies of the actual I/O code.
 */
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Warmup(iterations = 10, time = 1, timeUnit = TimeUnit.SECONDS)
@Measurement(iterations = 5, time = 2, timeUnit = TimeUnit.SECONDS)
@State(Scope.Thread)
public class SocketEventOverhead {

    @Fork(value = 1, jvmArgs = {
        "--add-exports",
        "java.base/jdk.internal.event=ALL-UNNAMED" })
    @Benchmark
    public int socketWriteJFRDisabled(SkeletonFixture fixture) {
        return fixture.write();
    }

    @Fork(value = 1, jvmArgs = {
        "--add-exports",
        "java.base/jdk.internal.event=ALL-UNNAMED",
        "-XX:StartFlightRecording:jdk.SocketWrite#enabled=false"})
    @Benchmark
    public int socketWriteJFREnabledEventDisabled(SkeletonFixture fixture) {
        return fixture.write();
    }

    @Fork(value = 1, jvmArgs = {
        "--add-exports",
        "java.base/jdk.internal.event=ALL-UNNAMED",
        "-XX:StartFlightRecording:jdk.SocketWrite#enabled=true,jdk.SocketWrite#threshold=1s"})
    @Benchmark
    public int socketWriteJFREnabledEventNotEmitted(SkeletonFixture fixture) {
        return fixture.write();
    }

    @Fork(value = 1, jvmArgs = {
        "--add-exports","java.base/jdk.internal.event=ALL-UNNAMED",
        "-XX:StartFlightRecording:jdk.SocketWrite#enabled=true,jdk.SocketWrite#threshold=0ms,disk=false,jdk.SocketWrite#stackTrace=false"})
    @Benchmark
    public int socketWriteJFREnabledEventEmitted(SkeletonFixture fixture) {
        return fixture.write();
    }

    @Fork(value = 1, jvmArgs = {
        "--add-exports",
        "java.base/jdk.internal.event=ALL-UNNAMED" })
    @Benchmark
    public int socketReadJFRDisabled(SkeletonFixture fixture) {
        return fixture.read();
    }

    @Fork(value = 1, jvmArgs = {
        "--add-exports",
        "java.base/jdk.internal.event=ALL-UNNAMED",
        "-XX:StartFlightRecording:jdk.SocketRead#enabled=false"})
    @Benchmark
    public int socketReadJFREnabledEventDisabled(SkeletonFixture fixture) {
        return fixture.read();
    }

    @Fork(value = 1, jvmArgs = {
        "--add-exports",
        "java.base/jdk.internal.event=ALL-UNNAMED",
        "-XX:StartFlightRecording:jdk.SocketRead#enabled=true,jdk.SocketRead#threshold=1s"})
    @Benchmark
    public int socketReadJFREnabledEventNotEmitted(SkeletonFixture fixture) {
        return fixture.read();
    }

    @Fork(value = 1, jvmArgs = {
        "--add-exports","java.base/jdk.internal.event=ALL-UNNAMED",
        "-XX:StartFlightRecording:jdk.SocketRead#enabled=true,jdk.SocketRead#threshold=0ms,disk=false,jdk.SocketRead#stackTrace=false"})
    @Benchmark
    public int socketReadJFREnabledEventEmitted(SkeletonFixture fixture) {
        return fixture.read();
    }

    /**
     * Fixture with fake read/write operations that have only the JFR event
     * boilerplate code for managing jfr events.  No actual transfer is done
     * to eliminate the I/O portion and measure the overhead of JFR event
     * handling in it's various states.
     */
    @State(Scope.Thread)
    public static class SkeletonFixture {

        private final InetSocketAddress remote = new InetSocketAddress("localhost",5000);

        public SocketAddress getRemoteAddress() {
            return remote;
        }

        public int write() {
            if (! SocketWriteEvent.enabled()) {
                return write0();
            }
            int nbytes = 0;
            long start = SocketWriteEvent.timestamp();
            try {
                nbytes = write0();
            } finally {
                long duration = start - SocketWriteEvent.timestamp();
                if (SocketWriteEvent.shouldCommit(duration)) {
                    SocketWriteEvent.emit(start, duration, nbytes, getRemoteAddress());
                }
            }
            return nbytes;
        }

        private int write0() {
            return 1024;
        }

        public int read() {
            if (! SocketReadEvent.enabled()) {
                return read0();
            }
            int nbytes = 0;
            long start = SocketReadEvent.timestamp();
            try {
                nbytes = read0();
            } finally {
                long duration = start - SocketReadEvent.timestamp();
                if (SocketReadEvent.shouldCommit(duration)) {
                    SocketReadEvent.emit(start, duration, nbytes, getRemoteAddress(), 0);
                }
            }
            return nbytes;
        }

        private int read0() {
            return 1024;
        }
    }
}