TestElasticTLAB.java

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/*
 * @test TestElasticTLAB
 * @key randomness
 * @summary Test that Shenandoah is able to work with elastic TLABs
 * @requires vm.gc.Shenandoah
 * @library /test/lib
 *
 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -XX:-UseTLAB -XX:-ShenandoahElasticTLAB -XX:+ShenandoahVerify TestElasticTLAB
 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -XX:-UseTLAB -XX:-ShenandoahElasticTLAB                       TestElasticTLAB
 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -XX:-UseTLAB -XX:+ShenandoahElasticTLAB -XX:+ShenandoahVerify TestElasticTLAB
 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -XX:-UseTLAB -XX:+ShenandoahElasticTLAB                       TestElasticTLAB
 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -XX:+UseTLAB -XX:-ShenandoahElasticTLAB -XX:+ShenandoahVerify TestElasticTLAB
 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -XX:+UseTLAB -XX:-ShenandoahElasticTLAB                       TestElasticTLAB
 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -XX:+UseTLAB -XX:+ShenandoahElasticTLAB -XX:+ShenandoahVerify TestElasticTLAB
 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -XX:+UseTLAB -XX:+ShenandoahElasticTLAB                       TestElasticTLAB
 */

import java.util.Random;
import jdk.test.lib.Utils;

public class TestElasticTLAB {

    static final long TARGET_MB = Long.getLong("target", 10_000); // 10 Gb allocation

    static volatile Object sink;

    public static void main(String[] args) throws Exception {
        final int min = 0;
        final int max = 384 * 1024;
        long count = TARGET_MB * 1024 * 1024 / (16 + 4 * (min + (max - min) / 2));

        Random r = Utils.getRandomInstance();
        for (long c = 0; c < count; c++) {
            sink = new int[min + r.nextInt(max - min)];
        }
    }

}