[Beowulf] NVIDIA GPUs, CUDA, MD5, and "hobbyists"

[Greg Lindahl]

On Wed, Jun 18, 2008 at 04:34:59PM -0700, Bill Broadley wrote:

> Cuda seems to take a different approach, instead of trying to 
> auto-parallelize
> a loop, it requires a function pointer to the code, and the function must
> declare it's exit condition.

In the end, CUDA doesn't end up being that much weirder than array
processors. Which were considered to be significantly harder to
program than, say, vector processors.

Your post talked about how difficult it was to write code that
worked. Well, the harder part is not getting some simple code written,
it's getting your actual algorithm into that straight-jacket, and
getting it to run fast.

If I had more free time, I'd experiment with getting my pretty simple
loopy hydrocode working. I suspect it would be pretty tedious, since
the 1D operator at the heart of the algorithm is 4,000 lines long.

-- greg