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→Assignment 3
=== Assignment 2 ===
We chose to move forward with the Jacobi Method for 2D Poisson Equations code.
We parallelized the original code by placing the jacobi calculations into a kernel. For this initial parallel version, we only used 1D threading and had each thread run a for loop for the other dimension.
[[File:Dps_915_gpusquad_ghostcellexample.png]]
We use a 1D grid of blocks which have 2D threads.
Thus the first block needs ghost cells on the right side, the last block needs ghost cells on the left side, and
all other blocks in the middle need ghost cells on both the left and right sides.
In A2 we only scaled the columns, but not the rows, they always stayed at 32. This made it easy for us to keep the grid one dimensional.
If we scaled the rows as well as the columns we would most likely have need to use a two dimensional grid of blocks.
This would make the problem more difficult as we would then not only need ghost columns, but also ghost rows on the top and bottom of blocks.
[[File:dps915_gpusquad_2Dghostcells.png]]
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