timed/networkdelta.c

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char sccsid[] = "@(#)networkdelta.c      2.3 (Berkeley) 6/18/88";
#endif /* not lint */

#include "globals.h"
#include <protocols/timed.h>

extern int machup;

/*
 * `networkdelta' selects the largest set of deltas that fall within the
 * interval RANGE, and uses them to compute the network average delta
 */

long networkdelta()
{
        int i, j, maxind, minind;
        int ext;
        int tempind;
        long tempdata;
        long x[NHOSTS];
        long average;

        for (i=0; i<slvcount; i++)
                x[i] = hp[i].delta;
        for (i=0; i<slvcount-1; i++) {
                tempdata = x[i];
                tempind = i;
                for (j=i+1; j<slvcount; j++) {
                        if (x[j] < tempdata) {
                                tempdata = x[j];
                                tempind = j;
                        }
                }
                x[tempind] = x[i];
                x[i] = tempdata;
        }

        /* this piece of code is critical: DO NOT TOUCH IT! */
/****/
        i=0; j=1; minind=0; maxind=1;
        if (machup == 2)
                goto compute;
        do {
                if (x[j]-x[i] <= RANGE)
                        j++;
                else {
                        if (j > i+1)
                                j--;
                        if ((x[j]-x[i] <= RANGE) && (j-i >= maxind-minind)) {
                                minind=i;
                                maxind=j;
                        }
                        i++;
                        if(i = j)
                                j++;
                }
        } while (j < machup);
        if ((x[machup-1] - x[i] <= RANGE) && (machup-i-1 >= maxind-minind)) {
                minind=i; maxind=machup-1;
        }
/****/
compute:
        ext = maxind - minind + 1;
        average = 0;
        for (i=minind; i<=maxind; i++)
                average += x[i];
        average /= ext;
        return(average);
}