Parallelism in Salmon Warren Approach
First you must decompose cells among processors which is nontrivial as irregular dynamic (maybe not in GEM) tree like structure
Originally used orthogonal recursive bisection chopping space succesively in 2 in different dimensions
However better to run “a space filling curve” through the cells and divide curve into chunks of equal work (which NOT equal numbers of particles as more computation in dense areas of particles)
- Note fast multipole essentially adds in nearby particles using “direct computation approach”
Simplest is to sort keys and divide up this sorted list (Morton curve)