1. Improving the Performance of Large-Scale Unstructured PDE Applications
Xing Cai
Simula Research Lab
Norway
June 18, 2004

2. How can parallel PDE solvers avoid overhead due to duplicated local computations?
Overlapping DD methods may involve duplicated local computations
Needed is a catagorization of the overlapping mesh points
Improved parallel performance is achievable

3. Overlapping DD methods are important parallel PDE solvers
Overlapping zones exist between neighbornig subdomains, sharing some mesh points => overhead

4. Avoiding overhead due to duplicated local computations needs a “categorization”
A disjoint distribution of all the overlapping points
Re-order the mesh points on each subdomain
Replace “work” on certain points with communication

5. Improved parallel performance arises from removing duplicated local computations
Fewer points participate in local computations
A slight increase of communication volume
Sequential software is easily re-usable