Additional Approaches to Make it Fast
Adjust both geometry and multipole order
- Use analytic error bound to make decisions concerning adequacy of approximation
Use space filling curves to map between memory and space
- Nearness in memory implies nearness in space
- An arbitrary region of space covers a small numbers of “segments” of memory
- Map “segments” to:
- cache lines = good cashe behavior
- processors = load balance, minimal communication
- pages = out-of-core computation
(memory is often more limiting than time)