MPI: Broadcast Communication

Listed below are MPI Broadcast communication times for a variety of message sizes and processor partitions. The total communication time is listed in terms of CPU clock cycles, and the bandwidth is listed in megabytes per second.

2 processors

  CPU cycles per word for 1 word messages is 11947.500000 (0.02 Mbytes/sec)
  CPU cycles per word for 2 word messages is 6007.500000 (0.04 Mbytes/sec)
  CPU cycles per word for 4 word messages is 2919.375000 (0.09 Mbytes/sec)
  CPU cycles per word for 8 word messages is 1485.000000 (0.18 Mbytes/sec)
  CPU cycles per word for 16 word messages is 742.500000 (0.36 Mbytes/sec)
  CPU cycles per word for 32 word messages is 396.562500 (0.68 Mbytes/sec)
  CPU cycles per word for 64 word messages is 217.265625 (1.24 Mbytes/sec)
  CPU cycles per word for 128 word messages is 116.015625 (2.33 Mbytes/sec)
  CPU cycles per word for 256 word messages is 64.072266 (4.21 Mbytes/sec)
  CPU cycles per word for 512 word messages is 37.705078 (7.16 Mbytes/sec)
  CPU cycles per word for 1024 word messages is 23.400879 (11.54 Mbytes/sec)
  CPU cycles per word for 2048 word messages is 19.281006 (14.00 Mbytes/sec)
  CPU cycles per word for 4096 word messages is 14.567871 (18.53 Mbytes/sec)
  CPU cycles per word for 8192 word messages is 11.667480 (23.14 Mbytes/sec)
  CPU cycles per word for 16384 word messages is 10.909424 (24.75 Mbytes/sec)
  CPU cycles per word for 32768 word messages is 9.514847 (28.38 Mbytes/sec)
  CPU cycles per word for 65536 word messages is 8.812408 (30.64 Mbytes/sec)
  CPU cycles per word for 131072 word messages is 8.644524 (31.23 Mbytes/sec)

4 processors

  CPU cycles per word for 1 word messages is 21735.000000 (0.01 Mbytes/sec)
  CPU cycles per word for 2 word messages is 10833.750000 (0.02 Mbytes/sec)
  CPU cycles per word for 4 word messages is 5416.875000 (0.05 Mbytes/sec)
  CPU cycles per word for 8 word messages is 2725.312500 (0.10 Mbytes/sec)
  CPU cycles per word for 16 word messages is 1358.437500 (0.20 Mbytes/sec)
  CPU cycles per word for 32 word messages is 687.656250 (0.39 Mbytes/sec)
  CPU cycles per word for 64 word messages is 384.960938 (0.70 Mbytes/sec)
  CPU cycles per word for 128 word messages is 197.226562 (1.37 Mbytes/sec)
  CPU cycles per word for 256 word messages is 116.015625 (2.33 Mbytes/sec)
  CPU cycles per word for 512 word messages is 70.400391 (3.84 Mbytes/sec)
  CPU cycles per word for 1024 word messages is 48.977051 (5.51 Mbytes/sec)
  CPU cycles per word for 2048 word messages is 44.197998 (6.11 Mbytes/sec)
  CPU cycles per word for 4096 word messages is 37.869873 (7.13 Mbytes/sec)
  CPU cycles per word for 8192 word messages is 32.827148 (8.22 Mbytes/sec)
  CPU cycles per word for 16384 word messages is 28.237610 (9.56 Mbytes/sec)
  CPU cycles per word for 32768 word messages is 27.873001 (9.69 Mbytes/sec)
  CPU cycles per word for 65536 word messages is 36.371269 (7.42 Mbytes/sec)
  CPU cycles per word for 131072 word messages is 40.421619 (6.68 Mbytes/sec)

8 processors

  CPU cycles per word for 1 word messages is 29835.000000 (0.01 Mbytes/sec)
  CPU cycles per word for 2 word messages is 14850.000000 (0.02 Mbytes/sec)
  CPU cycles per word for 4 word messages is 7576.875000 (0.04 Mbytes/sec)
  CPU cycles per word for 8 word messages is 3830.625000 (0.07 Mbytes/sec)
  CPU cycles per word for 16 word messages is 1864.687500 (0.14 Mbytes/sec)
  CPU cycles per word for 32 word messages is 999.843750 (0.27 Mbytes/sec)
  CPU cycles per word for 64 word messages is 550.546875 (0.49 Mbytes/sec)
  CPU cycles per word for 128 word messages is 296.894531 (0.91 Mbytes/sec)
  CPU cycles per word for 256 word messages is 170.332031 (1.59 Mbytes/sec)
  CPU cycles per word for 512 word messages is 111.796875 (2.42 Mbytes/sec)
  CPU cycles per word for 1024 word messages is 77.980957 (3.46 Mbytes/sec)
  CPU cycles per word for 2048 word messages is 79.332275 (3.40 Mbytes/sec)
  CPU cycles per word for 4096 word messages is 77.766724 (3.47 Mbytes/sec)
  CPU cycles per word for 8192 word messages is 334.179382 (0.81 Mbytes/sec)
  CPU cycles per word for 16384 word messages is 137.228851 (1.97 Mbytes/sec)
  CPU cycles per word for 32768 word messages is 82.006073 (3.29 Mbytes/sec)
  CPU cycles per word for 65536 word messages is 85.175285 (3.17 Mbytes/sec)
  CPU cycles per word for 131072 word messages is 66.956692 (4.03 Mbytes/sec)