Q-Logic IB6054601-00 D Switch User Manual


 
A – Benchmark Programs
Benchmark 3: Messaging Rate Microbenchmarks
A-4 IB6054601-00 D
Q
benchmark (as shown in the example above). It has been enhanced with the
following additional functionality:
Messaging rate reported as well as bandwidth
N/2 dynamically calculated at end of run
Allows user to run multiple processes per node and see aggregate bandwidth
and messaging rates
The benchmark has been updated with code to dynamically determine which
processes are on which host. This is an example showing the type of output you
will see when you run
mpi_multibw:
$ mpirun -np 8 ./mpi_multibw
This will run on four processes per node. Typical output might look like:
# PathScale Modified OSU MPI Bandwidth Test
(OSU Version 2.2, PathScale $Revision: 1.1 $)
# Running on 4 procs per node
# Size Aggregate Bandwidth (MB/s) Messages/s
1 8.150462 8150461.697283
2 16.693747 8346873.631841
4 33.086567 8271641.814960
8 66.733488 8341686.016159
16 108.097082 6756067.602089
32 213.733132 6679160.388156
64 389.544112 6086626.744516
128 569.671531 4450558.832794
256 725.826904 2835261.345093
512 839.450014 1639550.807757
1024 913.428063 892019.592596
2048 954.482747 466056.028717
4096 954.474461 233025.991467
8192 954.452712 116510.340772
16384 954.496729 58257.857017
32768 954.547225 29130.469523
65536 949.074433 14481.726572
131072 951.786548 7261.555084
262144 952.193849 3632.331272
524288 952.391830 1816.543255
1048576 952.490368 908.365600
2097152 952.539382 454.206172
4194304 952.566591 227.109573
Searching for N/2 bandwidth. Maximum Bandwidth of 954.547225
MB/s...
Found N/2 bandwidth of 476.993060 MB/s at size 94 bytes
This microbenchmark is available and can be downloaded from the QLogic website:
http://www.qlogic.com