Problems in Cut off Force Parallelism
Earthquakes cause load imbalance as “action” concentrated in processors where quake occurs
Can be addressed at cost of increasing communication by using “block-cyclic” decomposition so each processor gets part of action
Problem particularly bad for Monte Carlo as similar to classic “clustering algorithms” needed near critical points to get good performance. We know these have poor parallel performance
Long range versions of Monte Carlo will perform satisfactorily as can parallelize over long range force part of computation
Each color is area assigned to particular 1 of 4 processors. Star signifies Earthquake