SOFA: An Extensible Logical Optimizer for UDF-heavy Dataflows.

Recent years have seen an increased interest in large-scale analytical data flows on non-relational data. These data flows are compiled into execution graphs scheduled on large compute clusters. In many novel application areas the predominant building blocks of such data flows are user-defined predicates or functions (Udfs). However, the heavy use of Udfs is not well taken into account for data flow optimization in current systems.