Parallel Computing: Lecture 10

Learning objectives

After this class, you should be able to:

1. Describe common errors in MPI programs.
2. Debug parallel programs, using printfs and Totalview.
3. Analyze the performance of your code using performance analysis tools, such as hpmcount.

Reading assignment

1. Appendix C, web pages mentioned in ~ashoks/parco07/debug/README on the p690 at NCSA.
2. Chapter 6, section 6.2.

Exercises and review questions

• Questions on current lecture's material
  1. Run the example programs in ~ashoks/parco07/debug on the p690 at NCSA using the Totalview debugger, set breakpoints, step through code, and display the values of some variables.

• Questions on next lecture's material
  1. (Post your solution on the discussion board) Give an example of a graph with 5 vertices, and use Floyd's algorithm to find the shortest path between all pairs of vertices. Report the values obtained for these path.