org.commoncrawl.util.JVMStats.java Source code

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Here is the source code for org.commoncrawl.util.JVMStats.java

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/**
 * Copyright 2008 - CommonCrawl Foundation
 * 
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation, either version 3 of the License, or
 *    (at your option) any later version.
 *
 *    This program 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 for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 **/

package org.commoncrawl.util;

import java.lang.management.ManagementFactory;
import java.lang.management.MemoryMXBean;
import java.lang.management.MemoryUsage;
import java.lang.management.ThreadInfo;
import java.lang.management.ThreadMXBean;
import java.lang.management.GarbageCollectorMXBean;
import java.util.List;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Some basic JVM stats utilities
 * 
 * @author rana
 * 
 */
public class JVMStats {

    /** logging **/
    private static final Log LOG = LogFactory.getLog(JVMStats.class);

    private static final long MBytes = 1024 * 1024;

    private static long lastGCTime = 0;

    public static void dumpMemoryStats() {

        MemoryMXBean memoryMXBean = ManagementFactory.getMemoryMXBean();
        MemoryUsage memHeap = memoryMXBean.getHeapMemoryUsage();

        List<GarbageCollectorMXBean> gcBeans = ManagementFactory.getGarbageCollectorMXBeans();

        long gcTime = 0;
        for (GarbageCollectorMXBean gcBean : gcBeans) {
            gcTime += gcBean.getCollectionTime();
        }

        float utilizationRatio = ((float) memHeap.getUsed()) / ((float) memHeap.getMax());

        LOG.info("Heap Size:" + memHeap.getUsed() / MBytes + " (MB) CommitSize:" + memHeap.getCommitted() / MBytes
                + " (MB) Max:" + memHeap.getMax() + " Ratio:" + utilizationRatio + " GCTime:"
                + (gcTime - lastGCTime) + "PendingFinalCnt:" + memoryMXBean.getObjectPendingFinalizationCount());

        lastGCTime = gcTime;
    }

    public static float getHeapUtilizationRatio() {
        MemoryMXBean memoryMXBean = ManagementFactory.getMemoryMXBean();
        MemoryUsage memHeap = memoryMXBean.getHeapMemoryUsage();

        return ((float) memHeap.getUsed()) / ((float) memHeap.getMax());
    }

}