Simulation of collective operations hardware support for «Angara» interconnect

JSC NICEVT develops the Angara high-speed interconnect with multi-dimensional torus topology. To evaluate the performance of the interconnect on a large number of nodes a cycle-accurate simulator is used. Angara interconnect supports two types of collective operations:broadcast and reduce. The paper describes the implementation of collective operations in thesimulator and presents an early performance evaluation. Performance benchmarks include somebasic broadcast and all-reduce tests, as well as several well-known computational applications,specificaly, sparse matrix-vector multiplication and numerical solution of the nonlinear heatconduction equation.