I am facing very wierd results of OpenMPI 1.4.1 on Amazon EC2. I have
used Small Instance and and High CPU medium instance for benchmarking
latency and bandwidth. The OpenMPI was configured with the default
options. when the code is run in the cluster mode the latency and
bandwidth of Amazon EC2 Small instance is really less than that of
Amazon EC2 High CPU medium instance. To my understanding the
difference should not be that much. The following are the links to
graphs ad their data:
Please have a look on them.
Is anyone else facing the same problem. Any guidance in this regard
will highly be appreciated.
Centre for High Performance Scientific Computing,
School of Electrical Engineering and Computer Science,
National University of Sciences and Technology,
Office : +92 (51) 90852207