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BrookGPU: General Purpose Programming on GPUs
An anonymous reader writes "
BrookGPU is a compiler and runtime system that provides an easy, C-like programming environment (read: No GPU programming experience needed) for today's GPUs. A shader program running on the NVIDIA GeForce FX 5900 Ultra achieves over 20 GFLOPS, roughly equivalent to a 10 GHz Pentium 4. Combine this with the increased memory bandwidth, 25.3 GB/sec peak compared to the Pentium 4's 5.96 GB/sec peak, and you've got a seriously fast compute engine but programming them has been a real pain. BrookGPU adds simple data parallel language additions to C which allow programmers to specify certain parts of their code to run on the GPU. The compiler and runtime takes care of the rest. Here is the Project Page and Sourceforge page."
I wonder how long till we see a (insert worthwhile cause here)-At-Home client that supports this?
... can you say 'software synthesists' wet dream?
... $5 to the first person to use Brooke to make a synthesizer. :)
Oh, suddenly, that 'game investment' also gives you a few 100 extra voices of polyphony?
Sweet
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
but the link to the project page is correct.
Reminds me of the good old days when you used the processors in the C64 tapedrive to compute stuff. Wouldn't want to waste those precious cycles.
:)
I'm sure a lot of old farts will tell me how they used some serial controller to compute stuff back in the 60's and that I'm just a little kid.
Actually, since "graphics-related things" are all matrix operations, this would turn the GPU into a high-end vector (matrix) engine.
The dogcow says "Moof!"
A shader program running on the NVIDIA GeForce FX 5900 Ultra achieves over 20 GFLOPS, roughly equivalent to a 10 GHz Pentium 4.
wait, if there is a technology that allows construction of GPU that is 3 times faster than the fastest CPUs, why Intel and AMD do not use this technology to build those 3times faster CPUs?
are you sure that you can compare the speed of GPU and CPU?
#
#\ @ ? Colonize Mars
#
I'm completely new to meddling with graphics card, so apologies if this is a silly question: when programs utilising the GPU for arbitrary calculations are running does the screen go weird, or is there a way of stopping the output being displayed? A screenfull of junk might not matter to a scientist leaving their computer to crunch numbers for a few months but it wouldn't be good for a general-purpose program.
"'I pass the test,' she said. 'I will diminish, and go into the West, and remain Galadriel.'"
- JRR Tolkien.
"graphics-realted" things include things like floating point mathmatics, linear algebra, and vector operations. If you are doing anything computationally intensive, this might be usefull. You don't have to actually use the hardware to do anything graphical if you are just interested in turning numbers.
It would seem to me that the GPU is not going to be as general-purpose as the CPU, but could still attain the high mathematical throughput with vector-oriented processing.
Doing string searches, complex logic analyses, etc. would probably suck, but big data manipulations, such as SETI-style wave transformations, molecular analysis, etc., might be able to take advantage of them.
Design for Use, not Construction!
After taking a quick peek at the language part of the project it seems right now that most of it's functions are all about sets of data and how to move them around.
Makes sence of course as that is what a GPU is all about. (Yes I'm vastly over-simplyifying here.) So I would gather that it might be used for types of data that are streamed alot? Maybe used for video editing, real time video, etc where your trying to deal with a lot of data at once that your trying to move around and not just store or have to perform some more complicated types of functions upon.
However, I'm no 3d programmer and I should would love a more detailed analysis of the potentals for this.
Really, I know what I'm doing...Ohhhh, look at the shiny buttons!
...but I assume that in any advanced texturing/shading/bump mapping/other GFX function rendering, you apply all the different effects, and when you're done, specifically call that the frame is to be displayed on screen. (E.g. why your FPS != your monitor refresh rate)
I would assume that this program simply never calls the drawing function, but instead gets the results back from the GPU. The normal screen should be able to run in the meanwhile (I assume you can e.g. build a 3D environment while showing a 2D cutscreen), so I would think you can have a plain GUI, as long as it doesn't need to use anything advanced.
Kjella
Live today, because you never know what tomorrow brings
www.gpgpu.org
Very cool. Vector/Graphics processors could one day overtake General processors. They are way more energy efficient too.
Not to mention that you can put several PCI video cards in the same cheap PC. Multiply power by N.
I hadn't known there were so many idiots in the world until I started using the Internet -Stanislaw Lem
1) Each character would have it's own shader program.
2) You would set the shader program, draw a rectange, and the character would appear.
3) The shader programs would be automatically generated by processing TrueType files.
To implement:
1) Break Truetype outline up into a number of convex curve segments.
2) Each of these curve segments would be represented as a set of constants in the shader program
3) For each pixel, test a line from pixel to an edge.
4) If the number of segments crossed is odd the pixel is black else white.
The algorithm can be refined to add antialiasing and hinting.
What you end up with is text that is clear at any resolution. The size of the text is controlled by the rectangle you draw it in. The text can also be clearly rotated and sheared.
An obvious optimization is to get the GPU vendors to add a shader instruction to do the calculation for which side of the bezier curve segment the current point lies.
While not important for games drawing text is critical for desktops. And we all know about the current trends to draw desktops with 3D hardware.
This looks like a straightforward and clean extension that experienced C/C++ programmers won't find difficult to learn, but it isn't entirely clear to me whether just using this language, without any knowledge of GPU architecture, will lead to big improvements in performance. Granted, you don't need to know the details, but you've got to have an idea of what it is that you're trying to do and in a general way how the special constructs of the language allow you to do that. As with other such language extensions, you can nominally write in the language but not really use the extensions (how many "C++" programs have you seen that were really C programs with // comments and a few couts?) or use them in unintended ways that prevent the intended optimization. It seems to me that if the project really is aiming at programmers who are not familiar with GPUs, they need at least to provide a brief introduction to the special properties of GPU architecture and some guidelines as to how to use the features of the language to take advantage of them. At present I don't find this either on the web sites or in the distribution.
http://www.cs.unm.edu/~kmorel/documents/fftgpu/
The FFT on a GPU
This page contains supplemental material for the following paper.
Moreland, K and Angel, E. "The FFT on a GPU." In SIGGRAPH/Eurographics Workshop on Graphics Hardware 2003 Proceedings, pp. 112-119, July 2003.
I've always wondered why certain research programs (like Folding@home or SETI@home) don't use this type of code. My GPU sees more free time than my CPU plus it would probably get the work done faster. Also, imagine the speed increase of utilizing both the GPU and the CPU to their fullest potential. Now thats some fast folding!
SIGFAULT
Here is a Beyond3d link that has some opcode info. Look around their site for a NV30 vs R300 architecture document that has lots of great stuff. If you are looking for the best s/n ratio, Beyond3d is one of the best. All meat, little fanboyism.
PCI-X can fix this data bus in other ways as well. Motherboards come with one AGP slot, but PCI-X can and will provide many expansion slots.
Picture five high end GPUs on the motherboard eclipsing the single high-end cpu for a fraction of the price. Intel and AMD would be forced to cut the asking price of their products to compete. We could finally see some real four-way competition for "processors".
TW
WARNING: Lots of conjecture involved.
:)
That said, if you can fit your data sets and your program on to the video memory (128MB isn't uncommon on high-end), and you're doing lengthy calculations on these sets while being only interested in the results (again, not uncommon in HPC), then the relative slowness of reading these results back becomes a nonissue.
Does that help?
would the percision be enough though? as far as i know, GPU's do a lot of rounding off
Multiply power by N.
You work for Nvidia, don't you?
Forget thrust, drag, lift and weight. Airplanes fly because of money.
Researchers at Caltech and other institutions have been looking at this for about three years. See "Sparse Matrix Solvers on the GPU: Conjugate Gradients and Multigrid" by Bolz, Farmer, Grinspun and Schroder (SIGGRAPH 2003), for example. The paper, illustrations, and movies are available from Dr. Grinspun's homepage. The primary problems with the approach at the time this work was done was the limited bandwidth of texture-related operations in OpenGL based upon improper assumptions in pipeline optimization.
Joseph R. Kiniry
http://kind.ucd.ie/~kiniry/
Lecturer
UCD School of Computer Science and Informatics
This cluster has 70 Playstations (one article said that they'd ordered 100, but only 70 are in the cluster... Obviously the others are being used for "research".)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks