What does ping pong benchmark mean?
The ping pong benchmark is executed on two processes. From the client process a message (ping) is sent to the server process and then bounced back to the client (pong). MPI standard blocking send and receive is used. The ping-pong patterns are done in a loop. To achieve the communication time of one message, the total communication time is measured on the client process and divided by twice the loop length. Additional startup latencies are masked out by starting the measurement after one non-measured ping-pong. The benchmark in hpcc uses 8 byte messages and loop length = 8 for benchmarking the communication latency. The benchmark is repeated 5 times and the shortest latency is reported. To measure the communication bandwidth, 2,000,000 byte messages with loop length 1 are repeated twice.
