Parallel decomposition of unstructured FEM-meshes

  • Ralf Diekmann
  • Derk Meyer
  • Burkhard Monien
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 980)


We present a massively parallel algorithm for static and dynamic partitioning of unstructured FEM-meshes. The method consists of two parts. First a fast but inaccurate sequential clustering is determined which is used, together with a simple mapping heuristic, to map the mesh initially onto the processors of a massively parallel system. The second part of the method uses a massively parallel algorithm to remap and optimize the mesh decomposition taking several cost functions into account. It first calculates the amount of nodes that have to be migrated between pairs of clusters in order to obtain an optimal load balancing. In a second step, nodes to be migrated are chosen according to cost functions optimizing the amount and necessary communication and other measures which are important for the numerical solution method (like for example the aspect ratio of the resulting domains).

The parallel parts of the method are implemented in C under Parix to run on the Parsytec GCel systems. Results on up to 64 processors are presented and compared to those of other existing methods.


Parallel Adaptive Finite Element Simulations Parallel Mesh Decomposition Parallel Graph Partitioning Remapping/Repartitioning Dynamic Mapping 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Ralf Diekmann
    • 1
  • Derk Meyer
    • 1
  • Burkhard Monien
    • 1
  1. 1.Department of Mathematics and Computer ScienceUniversity of PaderbornGermany

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