The cmake_external_metis project provides a way to manage and build the METIS library, which is used for partitioning large-scale graphs and optimizing performance for parallel computing. It enables scalability analysis for high-performance computing by creating a partitioning of graphs that minimizes the communication cost between different parts of the graph.

The cmake_external_scotch project is a collection of tools for managing complex data structures, optimizing numerical simulations, and partitioning large graphs. It is built using the SCOTCH and PT-SCOTCH libraries, which provide efficient algorithms for graph partitioning, sparse matrix ordering, and related tasks.