As Zoltan is a general purpose parallel re-partitioning and data distribution library it is data agnostic. This means callback functions must be provided which Zoltan can query to retrieve the information it needs from the Fluidity data structures during the Zoltan library calls. There are four distinct sets of callback functions implemented in Fluidity; one set for load balancing and three sets for data migration, one for each of local nodes, halo nodes and fields.
It is not feasible to present full details of the implementation of each of the callback functions within this report. Instead a brief outline of the key callback functions will be presented here.