org/objectweb/proactive/loadbalancing/LoadMonitorLinux.java

/* 
 * ################################################################
 * 
 * ProActive: The Java(TM) library for Parallel, Distributed, 
 *            Concurrent computing with Security and Mobility
 * 
 * Copyright (C) 1997-2007 INRIA/University of Nice-Sophia Antipolis
 * Contact: proactive@objectweb.org
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or any later version.
 *  
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 * USA
 *  
 *  Initial developer(s):               The ProActive Team
 *                        http://www.inria.fr/oasis/ProActive/contacts.html
 *  Contributor(s): 
 * 
 * ################################################################
 */ 
package org.objectweb.proactive.loadbalancing;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;


public class LoadMonitorLinux{
    private double normaLoad;
    private RandomAccessFile statfile;

    public LoadMonitorLinux(LoadBalancer lb) {
       // this.lb = lb;
        this.normaLoad = 1.0;
        //load = 0;
        int nProcessors = 0;
        try {
                nProcessors = Runtime.getRuntime().availableProcessors();
                if (nProcessors > 1) this.normaLoad = 1/(1.0 * nProcessors);
            statfile = new RandomAccessFile("/proc/loadavg", "r");
            calculateLoad();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (NumberFormatException e) {
            e.printStackTrace();
                }
    }

    public synchronized double getLoad() {
        String cpuLine = null;
        try {
            statfile.seek(0);
            cpuLine = statfile.readLine();
        } catch (IOException e) {
            return 1;
        }

        double min1;
        
        java.util.StringTokenizer st = new java.util.StringTokenizer(cpuLine," ");
        min1 = Double.parseDouble(st.nextToken());

       return min1*normaLoad;
    }

    protected synchronized void calculateLoad() {

        double newload = getLoad();
       // load = newload;
    }
}

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