RB2D

The rb2D program is a 2D iterative solver which solves Laplace's equation using Gauss-Seidel's method with Red/Black ordering. The rb2D source is found in the directory http:./rb2D and you may also download a gzipped tar file in http:./rb2D.tar.gz The rb2D program supports various command line options to configure processor geometries and so on, which are similar to those employed in rb3D. Click HERE for an explanation of command line options and output format, but also look at the source code for the details. Note that there is only one cache blocking factor, and only 1 processor geometry specifier in two dimensions.

Running your program

Develop your code on a workstation and collect timing measurements of your running codes on the Cray T3E at SDSC. You may run interactively.

Be sure that the two environment variables SCACHE_D_STREAMS and MPI_BUFFER_MAX are cleared as shown or your message passing performance may suffer.

You can do this by putting the following lines in your .cshrc file:

# Be sure and run with the next two environment variables cleared to 0
# Turn off streams
setenv SCACHE_D_STREAMS 0

# Don't internally buffer messages
setenv MPI_BUFFER_MAX 0

If you have any problems, see the URL http://www.npaci.edu/News for up-to-date T3E info, or the URL http://www.npaci.edu/T3E for online T3E documentation.


Maintained by Scott B. Baden. Last modified: Thu Nov 20 18:56:09 PST 1997 Copyright (c) 1997, Scott B. Baden.