The VAMPIR and PARAVER Performance Analysis Software Applied to a Wet Chemical Etching Parallel Algorithm

J. C. Bruch, Jr.

Department of Mechanical and Environmental Engineering,

and Department of Mathematics

University of California, Santa Barbara, CA 93106

Abstract

        A wet chemical etching parallel algorithm is studied using performance analysis tools in order to optimize its performance.  The physical problem being solved is a moving boundary problem which is nonlinear and whose etching front is unknown a priori at each time.  A fixed domain formulation of the problem is discretized and the parallel solution algorithm is of successive over-relaxation type.  During the iteration process there is message-passing of data between the processors in order to update the calculations along the interfaces of the decomposed domains.  A key theoretical aspect of the approach is the application of a projection operator onto the positive solution domain.  This operation has to be applied at each iteration at each computational node.

        The VAMPIR and PARAVER performance analysis software are used to analyze and understand the execution behavior of the parallel algorithm such as:  communication patterns, processor load balance, computation versus, communication ratios, timing characteristics, and processor idle time.  This is all done by displays of post-mortem trace-files.  Performance bottlenecks can easily be identified at the appropriate level of detail.  This will numerically be demonstrated using example test data and comparisons of software capabilities will be made.