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

 *

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 * 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.

 *

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import java.util.List;

import java.lang.management.*;

import com.oracle.java.testlibrary.*;

import static com.oracle.java.testlibrary.Asserts.*;

/* @test TestPerfCountersAndMemoryPools

 * @bug 8023476

 * @summary Tests that a MemoryPoolMXBeans and PerfCounters for metaspace

 *          report the same data.

 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-UseCompressedOops -XX:-UseCompressedKlassPointers -XX:+UseSerialGC -XX:+UsePerfData TestPerfCountersAndMemoryPools

 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:+UseCompressedOops -XX:+UseCompressedKlassPointers -XX:+UseSerialGC -XX:+UsePerfData TestPerfCountersAndMemoryPools

 */

public class TestPerfCountersAndMemoryPools {

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

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

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

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

        }

    }

    private static MemoryUsage getMemoryUsage(String memoryPoolName) {

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

        for (MemoryPoolMXBean pool : pools) {

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

                return pool.getUsage();

            }

        }

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

                                   memoryPoolName);

    }

    private static void checkMemoryUsage(String memoryPoolName, String perfNS)

        throws Exception {

        // Need to do a gc before each comparison to update the perf counters

        System.gc();

        MemoryUsage mu = getMemoryUsage(memoryPoolName);

        assertEQ(getMinCapacity(perfNS), mu.getInit());

        System.gc();

        mu = getMemoryUsage(memoryPoolName);

        assertEQ(getUsed(perfNS), mu.getUsed());

        System.gc();

        mu = getMemoryUsage(memoryPoolName);

        assertEQ(getCapacity(perfNS), mu.getCommitted());

    }

    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();

    }

}