/************************************************************************************
*                    Micro Benchmark   mbcss
*                 -----------------------------   
* File name: mbcss.c
* Author   : Yuanhua Yu
* Date     : 20/12/1999.
*
*-------------------------------------------------------------------------------------
*
*  Function:  Measuring the set size of Cache Level-I and Level-II
*
*   Methods:  Sequential array read access
*
* Condition:  Running under Linux Operating System
*
*   History:  First version : 05/10/1999
*             Second version: 20/12/1999
*
*Parameters:  STRIDE       ---- intinial value of the stride : 8 (*4bytes)      
*             STEP_START   ---- initial value of the step    : (1024*32) bytes
*             TOTAL_ACCESS ---- number of the accesses done  : (32768*1024*16)
*
*  Variable:  arr_size     ---- size of the accessed array in bytes
*             arr_item     ---- arr_size = arr_size / (sizeof(ATYPE))(items)
*             step         ---- increment of size of the array
*
*************************************************************************************/

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <time.h>
#include <malloc.h>
#include <string.h>

#define STEP_START      (8*1024)          //bytes
#define STRIDE          8                 //*4 bytes
#define TOTAL_ACCESS    (1024*1024*32/2)  //operations
#define CACHE_SIZE_I    (1024*16)         //bytes
#define CACHE_SIZE_II   (1024*512)        //bytes
#define ATYPE long

/*----------------------------------------------------------------------------------*/

int main(char **av, int ac)
{
       volatile ATYPE  *va;
       register ATYPE  s1;
       register long	i;

       unsigned long start_time, stop_time;
       long          arr_size, arr_item, step;
       double	     time_cost, cost_per_op;

       FILE *fp;

       fp = fopen("Setsize_PIII500.dat","a+");
       fprintf(fp,"--------- Measurement of Cache Set_size ----------\n");
       fprintf(fp,"Array_size(bytes) Access_T(ns)  \tTotal_T(s)\n");
       printf("Step_size(byte)       Access_T(ns)  \tTotal_T(s)\n");

       for (step=STEP_START; step <= 16; step *= 2)
       {
  	         fprintf(fp,"step = %d\n", step);

	         for (arr_size=CACHE_SIZE_II/2; arr_size <= CACHE_SIZE_II*2; arr_size+=step)
             {
 	             arr_item = arr_size / (sizeof(ATYPE));
	             va = (ATYPE *) calloc(arr_item, sizeof(ATYPE));

                 for (i=0; i<arr_item; i+=STRIDE)   /* build up a sequential accessing   */
                      va[i] = i + STRIDE  ;         /* sequence                          */
                 va[i-STRIDE] = 0; 

	             s1 = 0;
	             start_time = clock();         
	             for (i=0; i<TOTAL_ACCESS; i+=8)    
	             {     
		              s1 = va[s1]; s1 = va[s1]; s1 = va[s1]; s1 = va[s1];
		              s1 = va[s1]; s1 = va[s1]; s1 = va[s1]; s1 = va[s1];
	             }
	             stop_time = clock();     

                 time_cost = ((double)(stop_time - start_time));
	             time_cost = time_cost/((double)CLOCKS_PER_SEC);
 	             cost_per_op = (1000000000.0*time_cost)/TOTAL_ACCESS;

                 printf("%10d\t\t%6.3f\t\t%6.3f %d\n",
	       	             arr_size,cost_per_op,time_cost,s1);
	             fprintf(fp,"%10d\t\t%6.3f\t\t%6.3f\n",
		                 arr_size,cost_per_op,time_cost);
             }
	         fprintf(fp,"\n");
       }

       fclose(fp);
       return 0;
}