UseCompressedOops.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
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 * 2 along with this work; if not, write to the Free Software Foundation,
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/*
 * @test
 * @bug 8022865
 * @summary Tests for different combination of UseCompressedOops options
 * @library /test/lib
 * @modules java.base/jdk.internal.misc
 *          java.management
 * @build sun.hotspot.WhiteBox
 * @run driver jdk.test.lib.helpers.ClassFileInstaller sun.hotspot.WhiteBox
 * @run main/othervm/timeout=480 -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. UseCompressedOops
 */
import java.util.ArrayList;
import java.util.Collections;
import jdk.test.lib.Platform;
import jdk.test.lib.process.ProcessTools;
import jdk.test.lib.process.OutputAnalyzer;
import sun.hotspot.gc.GC;

import sun.hotspot.code.Compiler;

public class UseCompressedOops {

    public static void main(String[] args) throws Exception {
        testCompressedOopsModesGCs();
        if (!Platform.isOSX() && !Platform.isAix()) {
            testCompressedOopsModesGCs("-XX:+UseLargePages");
        }
    }

    public static void testCompressedOopsModesGCs(String... flags) throws Exception {
        ArrayList<String> args = new ArrayList<>();
        Collections.addAll(args, flags);

        // Test default.
        testCompressedOopsModes(args);
        // Test GCs.
        testCompressedOopsModes(args, "-XX:+UseG1GC");
        testCompressedOopsModes(args, "-XX:+UseSerialGC");
        testCompressedOopsModes(args, "-XX:+UseParallelGC");
        if (GC.Shenandoah.isSupported()) {
            testCompressedOopsModes(args, "-XX:+UnlockExperimentalVMOptions", "-XX:+UseShenandoahGC");
        }
    }

    public static void testCompressedOopsModes(ArrayList<String> flags1, String... flags2) throws Exception {
        ArrayList<String> args = new ArrayList<>();
        args.addAll(flags1);
        Collections.addAll(args, flags2);

        if (Platform.is64bit()) {
            // Explicitly turn off compressed oops
            testCompressedOops(args, "-XX:-UseCompressedOops", "-Xmx32m")
                .shouldNotContain("Compressed Oops")
                .shouldHaveExitValue(0);

            // Compressed oops should be on by default
            testCompressedOops(args, "-Xmx32m")
                .shouldContain("Compressed Oops mode")
                .shouldHaveExitValue(0);

            // Explicly enabling compressed oops
            testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx32m")
                .shouldContain("Compressed Oops mode")
                .shouldHaveExitValue(0);

            // Skip the following seven test cases if we're on OSX or Windows.
            //
            // OSX doesn't seem to care about HeapBaseMinAddress.  Windows memory
            // locations are affected by ASLR.
            if (!Platform.isOSX() && !Platform.isWindows()) {

                // Larger than 4gb heap should result in zero based with shift 3
                testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx5g")
                    .shouldContain("Zero based")
                    .shouldContain("Oop shift amount: 3")
                    .shouldHaveExitValue(0);

                // Larger than 3gb heap and HeapBaseMinAddress=1g should result in zero based with shift 3
                testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx3200m", "-XX:HeapBaseMinAddress=1g")
                    .shouldContain("Zero based")
                    .shouldContain("Oop shift amount: 3")
                    .shouldHaveExitValue(0);

                // Small heap above 4gb should result in zero based with shift 3
                testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx32m", "-XX:HeapBaseMinAddress=4g")
                    .shouldContain("Zero based")
                    .shouldContain("Oop shift amount: 3")
                    .shouldHaveExitValue(0);

                // Small heap above 32gb should result in non-zero based with shift 3
                testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx32m", "-XX:HeapBaseMinAddress=32g")
                    .shouldContain("Non-zero disjoint base")
                    .shouldContain("Oop shift amount: 3")
                    .shouldHaveExitValue(0);

                // Small heap above 32gb should result in non-zero based with shift 3
                testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx32m", "-XX:HeapBaseMinAddress=72704m")
                    .shouldContain("Non-zero based")
                    .shouldContain("Oop shift amount: 3")
                    .shouldHaveExitValue(0);

                // 32gb heap with heap base above 64gb and object alignment set to 16 bytes should result
                // in non-zero based with shift 4
                testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx32g", "-XX:ObjectAlignmentInBytes=16",
                               "-XX:HeapBaseMinAddress=64g")
                    .shouldContain("Non-zero disjoint base")
                    .shouldContain("Oop shift amount: 4")
                    .shouldHaveExitValue(0);

                // 32gb heap with object alignment set to 16 bytes should result in zero based with shift 4
                testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx32g", "-XX:ObjectAlignmentInBytes=16")
                    .shouldContain("Zero based")
                    .shouldContain("Oop shift amount: 4")
                    .shouldHaveExitValue(0);
            }

            // This is a pathologic case for the heap allocation algorithm. Regression test.
            // HeapBaseMinAddress must be 2g and should not be set on the command line.
            testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx2g")
                .shouldNotContain("Max heap size too large for Compressed Oops")
                .shouldHaveExitValue(0);
            testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx29g", "-XX:CompressedClassSpaceSize=1g")
                .shouldNotContain("Max heap size too large for Compressed Oops")
                .shouldHaveExitValue(0);

            // Explicitly enabling compressed oops with 32gb heap should result a warning
            testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx32g")
                .shouldContain("Max heap size too large for Compressed Oops")
                .shouldHaveExitValue(0);

            // 32gb heap should not result a warning
            testCompressedOops(args, "-Xmx32g")
                .shouldNotContain("Max heap size too large for Compressed Oops")
                .shouldHaveExitValue(0);

            // Explicitly enabling compressed oops with 32gb heap and object
            // alignment set to 8 byte should result a warning
            testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx32g", "-XX:ObjectAlignmentInBytes=8")
                .shouldContain("Max heap size too large for Compressed Oops")
                .shouldHaveExitValue(0);

            // 64gb heap and object alignment set to 16 bytes should result in a warning
            testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx64g", "-XX:ObjectAlignmentInBytes=16")
                .shouldContain("Max heap size too large for Compressed Oops")
                .shouldHaveExitValue(0);

        } else {
            // Compressed oops should only apply to 64bit platforms
            testCompressedOops(args, "-XX:+UseCompressedOops", "-Xmx32m")
                .shouldContain("Unrecognized VM option 'UseCompressedOops'")
                .shouldHaveExitValue(1);
        }
    }

    private static OutputAnalyzer testCompressedOops(ArrayList<String> flags1, String... flags2) throws Exception {
        ArrayList<String> args = new ArrayList<>();

        // Always run with these two:
        args.add("-Xlog:gc+heap+coops=trace");
        args.add("-Xms32m");

        // Add the extra flags
        args.addAll(flags1);
        Collections.addAll(args, flags2);

        args.add("-version");

        ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(args);
        return new OutputAnalyzer(pb.start());
    }
}