1. A computer-implemented method of improving performance of schema matching, comprising: storing, by a computer system, a matching topology that maps a first data structure to a second data structure; identifying, by the computer system, a first portion of the matching topology that is a candidate for improvement as determined according to an incidence graph, wherein the incidence graph comprises a plurality of nodes, a plurality of edges between the plurality of nodes, a plurality of average runtimes associated with the plurality of nodes, and a plurality of speedup values associated with the plurality of edges; and rewriting, by the computer system, the first portion of the matching topology with a second portion according to the incidence graph.