/*

 * Copyright (c) 2013, 2019, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package gc.metaspace;

import java.util.List;

import java.lang.management.*;

import jdk.test.lib.Platform;

import static jdk.test.lib.Asserts.*;

import gc.testlibrary.PerfCounters;

/* @test TestPerfCountersAndMemoryPools

 * @bug 8023476

 * @library /test/lib /

 * @requires vm.gc.Serial

 * @summary Tests that a MemoryPoolMXBeans and PerfCounters for metaspace

 *          report the same data.

 * @modules java.base/jdk.internal.misc

 *          java.management

 *          jdk.internal.jvmstat/sun.jvmstat.monitor

 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-UseCompressedOops -XX:-UseCompressedClassPointers -XX:+UseSerialGC -XX:+UsePerfData -Xint gc.metaspace.TestPerfCountersAndMemoryPools

 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:+UseCompressedOops -XX:+UseCompressedClassPointers -XX:+UseSerialGC -XX:+UsePerfData -Xint gc.metaspace.TestPerfCountersAndMemoryPools

 */

public class TestPerfCountersAndMemoryPools {

    public static void main(String[] args) throws Exception {

        checkMemoryUsage("Metaspace", "sun.gc.metaspace");

        if (InputArguments.contains("-XX:+UseCompressedClassPointers") && Platform.is64bit()) {

            checkMemoryUsage("Compressed Class Space", "sun.gc.compressedclassspace");

        }

    }

    private static MemoryPoolMXBean getMemoryPool(String memoryPoolName) {

        List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();

        for (MemoryPoolMXBean pool : pools) {

            if (pool.getName().equals(memoryPoolName)) {

                return pool;

            }

        }

        throw new RuntimeException("Excpted to find a memory pool with name " +

                                   memoryPoolName);

    }

    private static void checkMemoryUsage(String memoryPoolName, String perfNS)

        throws Exception {

        MemoryPoolMXBean pool = getMemoryPool(memoryPoolName);

        // First, call all the methods to let them allocate their own slab of metadata

        getMinCapacity(perfNS);

        getCapacity(perfNS);

        getUsed(perfNS);

        pool.getUsage().getInit();

        pool.getUsage().getUsed();

        pool.getUsage().getCommitted();

        assertEQ(1L, 1L, "Make assert load");

        // Must do a GC to update performance counters

        System.gc();

        assertEQ(getMinCapacity(perfNS), pool.getUsage().getInit(), "MinCapacity out of sync");

        // Adding a second GC due to metadata allocations caused by getting the

        // initial size from the pool. This is needed when running with -Xcomp.

        System.gc();

        assertEQ(getUsed(perfNS), pool.getUsage().getUsed(), "Used out of sync");

        assertEQ(getCapacity(perfNS), pool.getUsage().getCommitted(), "Committed out of sync");

    }

    private static long getMinCapacity(String ns) throws Exception {

        return PerfCounters.findByName(ns + ".minCapacity").longValue();

    }

    private static long getCapacity(String ns) throws Exception {

        return PerfCounters.findByName(ns + ".capacity").longValue();

    }

    private static long getUsed(String ns) throws Exception {

        return PerfCounters.findByName(ns + ".used").longValue();

    }

}