parallel computation

Hi Shen Weigang,

Yes, parallel computation definitely still works for ESyS-Particle however you are unlikely to observe a significant speedup for a 1M particle simulation using 8 cores.

ESyS-Particle demonstrates so-called "weak scalability" rather than "strong scalability". Benchmarking of ESyS-Particle on up to 32,000 cores demonstrates that the best speedup is obtained if the number of particles per worker (or core) is around 10000. Consequently, I would be looking to use approximately 100 cores for a 1M particle simulation. This will ensure that the simulation will take approximately the same amount of time as a 10000 particle simulation using a single worker process.

I would estimate that running your 1M particle simulation on 8 cores would be roughly equivalent to running a 125,000 particle simulation on a single core. This will be quite slow for most DEM problems; likely requiring a week or more of execution time depending on the number of timesteps to be simulated.

My suggestion would therefore be to either port your simulation to a supercomputer where more cores are available, or reduce your problem size to approximately 100,000 particles (around 12,500 particles per worker for 8 cores).

I hope this helps. Have fun!

Cheers,

Dion