Mar 11, 2025

The hash function computation is negligible - the additional header mmap and the false positive conflict resolution searches are the real cost. I set up a simulation to measure these. The header cost is simulated by doubling the 4GB tx header bucket count. This reduce conflicts in that table, but while fully keeping the additional 4GB in RAM. Performance improvement from the reduced conflicts in that table is minimal, as previously measured. So that handles the filter. Then the false positive searches are simulated by using the hash table hash function result for the point table write, and modulo to make an existence check call for 0.29% of all inserts to the point table. If that performs well, this should certainly do the same.