time_cilk.cilk

FFTW, a collection of fast C routines to compute the Discrete Fourier Transform in one or more dime

/*
 * Copyright (c) 1997-1999, 2003 Massachusetts Institute of Technology
 *
 * 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 2 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <cilk.h>
#include <cilk-lib.h>

#include <stdio.h>
#include <math.h>

#include "fftw_cilk.cilkh"

#define NUM_ITER 5000000L

#define N_TESTS_1D 16
#define N_TESTS_3D 9

extern void initialize_fft_data(fftw_complex * arr, long n);

cilk int main(int argc, char **argv)
{
     int n1[N_TESTS_1D] =
          {
               16,
               32,
               64,
               128,
               256,
               512,
               1024,
               2048,
               4096,
               8192,
               16384,
               32768,
               65536,
               131072,
               262144,
               524288
          };
     int n3[N_TESTS_3D][3] =
          {
               { 16, 16, 16 },
               { 24, 24, 24 },
               { 32, 32, 32 },
               { 49, 49, 49 },
               { 64, 64, 64 },
               { 80, 80, 80 },
               {100,100,100 },
               {128, 128, 128 },
               {256, 256, 256 },
          };
     int i, test, iter, max_iter;
     Cilk_time start_t, end_t, init_t;
     fftw_complex *cin, *out;
     double time_scale, time1, time2;
     int max_size;
     fftw_plan plan;
     fftwnd_plan plan_nd;

     /*************** Benchmark fftw_cilk ****************/
     max_size = 0;
     for (i = 0; i < N_TESTS_1D; ++i)
          if (n1[i] > max_size)
               max_size = n1[i];

     cin = malloc(max_size * sizeof(fftw_complex));
     out = malloc(max_size * sizeof(fftw_complex));

     if (!cin || !out) {
          printf("Not enough memory!  At least %d bytes needed.\n",
                 max_size * sizeof(fftw_complex) * 2);
          exit(1);
     }
     printf("%15s%20s%20s%20s\n", "Array Size", "FFTW", "FFTW_CILK",
            "Speedup Factor");

     for (test = 0; test < N_TESTS_1D; ++test) {
          printf("%15d", n1[test]);
          fflush(stdout);

          plan = fftw_create_plan(n1[test], FFTW_FORWARD, FFTW_MEASURE);

          max_iter = NUM_ITER / (n1[test] * log(2.0 * n1[test]));

          if (max_iter < 1)
               max_iter = 1;

          time_scale = 1.0e6 / (max_iter * (log(n1[test])/log(2.0) * n1[test]));

          initialize_fft_data(cin, n1[test]);
          start_t = Cilk_get_wall_time();
          for (iter = 0; iter < max_iter; ++iter)
               initialize_fft_data(cin, n1[test]);
          end_t = Cilk_get_wall_time();
          init_t = end_t - start_t;

          /* Time FFTW: */

          initialize_fft_data(cin, n1[test]);
          fftw(plan, 1, cin, 1, 0, out, 1, 0);
          start_t = Cilk_get_wall_time();
          for (iter = 0; iter < max_iter; ++iter) {
               initialize_fft_data(cin, n1[test]);
               fftw(plan, 1, cin, 1, 0, out, 1, 0);
          }
          end_t = Cilk_get_wall_time();
          printf("%20g", time1 =
                      Cilk_wall_time_to_sec(end_t - start_t - init_t) *
                      time_scale);
          fflush(stdout);

          /* Time Cilk FFTW: */

          initialize_fft_data(cin, n1[test]);
          spawn fftw_cilk(plan, 1, cin, 1, 0, out, 1, 0);
          sync;
          start_t = Cilk_get_wall_time();
          for (iter = 0; iter < max_iter; ++iter) {
               initialize_fft_data(cin, n1[test]);
               spawn fftw_cilk(plan, 1, cin, 1, 0, out, 1, 0);
               sync;
          }
          end_t = Cilk_get_wall_time();
          printf("%20g", time2 =
                      Cilk_wall_time_to_sec(end_t - start_t - init_t) *
                      time_scale);
          printf("%20g\n",time1/time2);
          fflush(stdout);



#if CILK_CRITICAL_PATH > 0  /* if critical path is measured */
	  {
	       Cilk_time begin_work, end_work;
	       Cilk_time begin_cp, end_cp;

	       /* measure work and CP */
	       sync;
	       begin_cp = Cilk_user_critical_path;
	       begin_work = Cilk_user_work;
	       spawn fftw_cilk(plan, 1, cin, 1, 0, out, 1, 0);
	       sync;
	       end_cp = Cilk_user_critical_path;
	       end_work = Cilk_user_work;

	       printf("Work = %f s\n",
		      Cilk_time_to_sec(end_work - begin_work));
	       printf("Critical path = %f s\n",
		      Cilk_time_to_sec(end_cp - begin_cp));
	       printf("Average parallelism = %f\n",
		      Cilk_time_to_sec(end_work - begin_work) /
		      Cilk_time_to_sec(end_cp - begin_cp));
	  }
#endif

          /* Done. */


          fftw_destroy_plan(plan);
     }

     free(cin);
     free(out);

     /*************** Benchmark fftwnd_cilk ****************/
     printf("\n");

     max_size = 0;
     for (i = 0; i < N_TESTS_3D; ++i)
          if (n3[i][0]*n3[i][1]*n3[i][2] > max_size)
               max_size = n3[i][0]*n3[i][1]*n3[i][2];

     cin = malloc(max_size * sizeof(fftw_complex));

     if (!cin) {
          printf("Not enough memory!  At least %d bytes needed.\n",
                 max_size * sizeof(fftw_complex));
          exit(1);
     }
     printf("%15s%20s%20s%20s\n", "Array Size", "FFTWND", "FFTWND_CILK",
            "Speedup Factor");

     for (test = 0; test < N_TESTS_3D; ++test) {
          int N; {
               char s[20];
               sprintf(s,"%dx%dx%d",n3[test][0],n3[test][1],n3[test][2]);
               printf("%15s",s);
          }
          fflush(stdout);

          plan_nd = fftwnd_create_plan(3,n3[test], FFTW_FORWARD,
                                       FFTW_IN_PLACE | FFTW_MEASURE);

          N = n3[test][0]*n3[test][1]*n3[test][2];

          max_iter = NUM_ITER / (N * log(2.0 * N));

          if (max_iter < 1)
               max_iter = 1;

          time_scale = 1.0e6 / (max_iter * (log(N)/log(2.0) * N));

          initialize_fft_data(cin, N);
          start_t = Cilk_get_wall_time();
          for (iter = 0; iter < max_iter; ++iter)
               initialize_fft_data(cin, N);
          end_t = Cilk_get_wall_time();
          init_t = end_t - start_t;

          /* Time FFTW: */

          initialize_fft_data(cin, N);
          fftwnd(plan_nd, 1, cin, 1, 0, out, 1, 0);
          start_t = Cilk_get_wall_time();
          for (iter = 0; iter < max_iter; ++iter) {
               initialize_fft_data(cin, N);
               fftwnd(plan_nd, 1, cin, 1, 0, out, 1, 0);
          }
          end_t = Cilk_get_wall_time();
          printf("%20g", time1=Cilk_wall_time_to_sec(end_t - start_t - init_t) *
                               time_scale);
          fflush(stdout);

          /* Time Cilk FFTW: */

          initialize_fft_data(cin, N);
          spawn fftwnd_cilk(plan_nd, 1, cin, 1, 0, 0, 0, 0);
          sync;
          start_t = Cilk_get_wall_time();
          for (iter = 0; iter < max_iter; ++iter) {
               initialize_fft_data(cin, N);
               spawn fftwnd_cilk(plan_nd, 1, cin, 1, 0, 0, 0, 0);
               sync;
          }
          end_t = Cilk_get_wall_time();
          printf("%20g", time2=Cilk_wall_time_to_sec(end_t - start_t - init_t) *
                               time_scale);

          /* Done. */

          printf("%20g\n",time1/time2);
          fflush(stdout);

          fftwnd_destroy_plan(plan_nd);
     }

     free(cin);

     return 0;
}

void initialize_fft_data(fftw_complex * arr, long n)
{
     long i;

     for (i = 0; i < n; i++) { /* initialize to some arbitrary values: */
          c_re(arr[i]) = 0.56923456;
          c_im(arr[i]) = 0.23858572;
     }
}