Speaker
Description
I discuss solving large-scale symmetric and positive definite eigenproblems in distributed computing environments where communication between tasks is expensive, such as a cluster of networked workstations running the HTCondor batch system. As a model problem, I consider computing a few smallest eigenvalues of several eigenproblems related to FE-discretization of elliptic PDEs. The matrices are exported from COMSOL.
In particular, I develop a Ritz method using method subspace constructed from local spaces associated with non-overlapping partitions of the connectivity graph of the matrix. I discuss a technique for constructing these local subspaces from boundary-to-interior mapping related to the subdomain. I give an outline of error analysis and report numerical tests conducted on a cluster at Aalto University.