About

A benchmark helps to mesure and compare the implemented design among others. Latency and throughput are important factors for a network protocol.

Testing

Once the module is built, it must be loaded on both machines before it can be used. To accomplish this, a script was written that automatically copies the module to the /cplant/modules directory as well as the corresponding directory on the other machine (test programs are also copied at this point), unloads the previous modules if they are still running and loads the new module along with several others. Because Portals 3 is still in the development stage, other modules are required to perform fundamental tasks. For example, the old Portals 2 module is sometimes used to initiate a job by synchronizing information on both nodes. This and other helper modules are loaded in the following order: portals.mod (Portals 2), rtscts.mod, myrIP.mod and, finally, the new P3oT.mod is loaded last.

With the help of the Portals 2 module, a test program can be run atomically from the Portals 3 testing directory. These tests are compiled together into p3test, so they can be run one after the other and test all aspects of the Portals implementation. Using this program, preliminary results show a latency of around 80 microseconds for the P3oT module. It should be noted that this figure comes from an initial implementation with no optimizations and which still includes one memory copy to or from the CMB per node and an OS call upon sending. When these time consuming activities are circumvented, the latency will be much less.