1 | The Pipeline method has high communication costs (as will in fact use "block cyclic" to preserve locality) and is complex to implement well |
2 | Thus instead we note that we can get new versions of Gauss Seidel by reordering update order -- this could (in principle) make for a better or worse method (or more likely we won't know if better or worse!) |
3 | There is a natural reordering which is typically as good if not better for which parallelism is "trivial" |
4 | This ONLY works for nearest neighbor stencil but there are versions of red black for similar stencils |