ylfink@water.waterloo.edu (ylfink) (10/03/88)
DEPARTMENT OF COMPUTER SCIENCE
UNIVERSITY OF WATERLOO
SEMINAR ACTIVITIES
SCIENTIFIC COMPUTATION SEMINAR
- Thursday, October 6, 1988
Dr. Eleanor Chu, a member of this department, will
speak on
``Parallel QR Factorization on a Shared-memory MIMD
Computer''.
TIME: 4:00 PM
ROOM: DC 1304
ABSTRACT
A new algorithm for computing an orthogonal
decomposition of a rectangular mxn matrix A on a
--- -
shared-memory multiprocessor is presented. The
algorithm uses Givens rotations, and has the feature
that its synchronization cost is independent of the row
dimension of the matrix. We shall show that there are
a number of ways to implement the proposed algorithm,
and that the suitability of an implementation is
determined by the synchronization cost of a particular
machine. Our analysis of work load distribution and
performance indicates that the algorithm is effective
in balancing the load and producing high efficiency
(speed-up). We shall describe the key ideas used in
conducting such analyses and present the complexity
results. Finally, we provide implementation details
and experimental results on a Sequent Balance 8000
multiprocessor.