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CUDA MapReduce NVIDIA Python

MapReduce on CUDA using Python (and a Discontinuous Galerkin solver!)

As volcore pointed out, there is a library called pycuda, which allows for CUDA programming in Python. It also comes with a nice ReductionKernel class, which allows one to rapidly develop custom MapReduce kernels.

Update: Even better, the same author has published a Discontinuous Galerkin solver, based on the same stuff. This can be used to solve partial differential equations, e.g. for fluid simulations, but also for EM simulations, using Maxwell’s equations.

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ATI Bug NVIDIA OpenGL OS X

GLSL bugs in OS X still there

 Some time back I reported on crashing the Macs here using a non-trivial GLSL shader program. This bug still exists to this day. Now we’ve got a small, brand new 21″ iMac, fresh out of the box. It exhibits a similar problem. This time, the UI does not lock up, but the rendering is totally borked. Compare the two screenshots. The first one shows the correct rendering, on a Linux PC using an NVIDIA GTX285 GPU, the other one is from the 21″ iMac using an ATI GPU. The trick between crashing and not crashing seems to be the ATI brand…

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NVIDIA OS X

OS X graphics driver bugs

On both our MBP as well as our iMac I can get OS X to crash when using a perfectly fine fragment shader, which works well under Linux. Both under Linux as well as under OS X I am using NVIDIA hardware. This is what the crash looks like:

OS X crashing when using complex GLSL shaders from Arne Schmitz on Vimeo.

Update 2010-07-13: Apple already wrote back, and requested a sample app, which I provided. Let’s see if they can figure this out. Kudos for reacting so quickly!