Hi all,

Like a few of you already know, I'm currently working on a GPU port of the seti app, targeted at nVidias 8800 series of graphics cards.

I've already ported the 2 most trivial crunching steps - chirping and calculating the power spectrum - and created a little test app.

The app just generates some text output, it is _no_ replacement for the seti app.

If you have an 8800 card, it would be nice if you'd do a test run.

The app, and sources, are available at Anton's site

The whole port is pretty much a work in progress. Comments and suggestions are very welcome.

Regards Hans

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Great to see you making progress, Hans!
Any news on the Linux front?

Regards,
Simon.

P.S.: I see Anton's site is using Enigma, a portal I co-develop :o) I may be able to help with the site theme if necessary.

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Great to see you making progress, Hans!
Any news on the Linux front?

Regards,
Simon.

P.S.: I see Anton's site is using Enigma, a portal I co-develop :o) I may be able to help with the site theme if necessary.

I'm trying to wrap my mind around the FFT ATM, but making good progress - at least I hope so :o)

I should have something presentable by the end of next week....


Regards Hans

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This is sounding rather good.

I'll hold out on the next upgrade a short while to go with an 8800 series GPU or better... whichever your code fits.

Good luck with the code!

Regards,
Martin

(Stuck elsewhere in EDF :-( )

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Random thought:

What happened to Eric K's work on doing this for the previous vector-based GPUs?
And would that be of any help?

Regards,
Martin

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See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

Random thought:

What happened to Eric K's work on doing this for the previous vector-based GPUs?
And would that be of any help?

Regards,
Martin

I've tried reading the sources of GPUFFTW, but it gave me a headache.
Crunching via OpenGL apparently is not for the faint of heart :o)

There's a tiny chance that we can backport some of the code to CG, but I'm not positive about that yet.

Regards Hans

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I've tried reading the sources of GPUFFTW, but it gave me a headache.

You have my sympathies. The first "F" in "FFT" gave me butterflies!

Crunching via OpenGL apparently is not for the faint of heart :o)

There's a tiny chance that we can backport some of the code to CG, but I'm not positive about that yet.

Interesting. Would that code still work as intended despite the very different GPU architecture? I guess you at least get the advantage of the faster PCI-E transfers.

Good luck for the coding!

Regards,
Martin

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See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

I've tried reading the sources of GPUFFTW, but it gave me a headache.
Crunching via OpenGL apparently is not for the faint of heart :o)

There's a tiny chance that we can backport some of the code to CG, but I'm not positive about that yet.

Regards Hans

User Benher claimed here that there exists open source for FFT in the GPU. Is that the GPUFFTW that you mentioned?

User Benher claimed here that there exists open source for FFT in the GPU. Is that the GPUFFTW that you mentioned?

Yep. It's one of them, reportedly the fastest.
You can download a copy from here after filling out a really short form :o)

Both windows and linux are supported.
I tried using it for seti, but could get no speed improvement, mainly because of the overhead introduced by transferring and rearranging data.

Regards Hans

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You have my sympathies. The first "F" in "FFT" gave me butterflies!

Hahahaha! Very good! :-)

Well done!

I know that this'll sound like nit-picking or down-putting, but please don't forget the Mac OS (especially PowerPC).

Keep up the good work!

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Yep. It's one of them, reportedly the fastest.
You can download a copy from here after filling out a really short form :o)

Both windows and linux are supported.
I tried using it for seti, but could get no speed improvement, mainly because of the overhead introduced by transferring and rearranging data.

Regards Hans

This is BRUTAL -- the computations are based on OpenGL.

Is there an easier approach using the mathematical routines in CUDA? I realize you can't disclose much 'cause of NDA required to use CUDA, but some general direction would be great.

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quite interesting to say the least....I have two questions:

1) With the possibilities of dual cards in a system can/will that cause issues?

2) When/if GPU crunching is complete will there be a version for "older" cards (i.e. 7600, 7800, 7900)????

-citroja

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GPU crunching might only be practical on PCI Express based cards because AGP has low GPU to main memory bandwidth.

Eric

quite interesting to say the least....I have two questions:

1) With the possibilities of dual cards in a system can/will that cause issues?

2) When/if GPU crunching is complete will there be a version for "older" cards (i.e. 7600, 7800, 7900)????

-citroja

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@SETIEric@qoto.org (Mastodon)

Hi,

I've stumbled upon a site that may have an interesting product to help in developing for massively parallel architectures like new GPUs and the Cell BE (read: PS3).

The site is http://www.rapidmind.net. I've applied for and received an evaluation license from them.

The basic idea behind this product is that you can write your code in "normal" C++ and have the same code work on any supported architecture! That is to say, you write one codebase, do not have to use specialized architectural tools or languages, do not have to learn all sorts of platform-specific concepts you don't really need, ...

Supported platforms: all ATI Radeon 1x00s, nVidia GeForce 6xxx/7xxx (and I assume, 8xxx as well) GPUs as well as Cell BE-based systems.

Now, I haven't received a price quote yet, so I don't exactly know how expensive their product is (though I will find out). If it's less than 1000 bucks, it may be worth it (though I'd definitely like to test/benchmark before I spend any money).

In any case, even just using the Eval version may give people working on these implementations some pointers (checking out what RapidMind's code does vs. their own for the same things) to get started.

Of course, hand-tuned code may still be quicker than what their product comes up with - but contrast that with the development time delta, and the picture may change.

Regards,
Simon.

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GPU crunching might only be practical on PCI Express based cards because AGP has low GPU to main memory bandwidth.

Eric

quite interesting to say the least....I have two questions:

1) With the possibilities of dual cards in a system can/will that cause issues?

2) When/if GPU crunching is complete will there be a version for "older" cards (i.e. 7600, 7800, 7900)????

-citroja

The 7600s, 7800s, and 7900s all have PCIe versions (to my knowledge) I have a 7800 GTX and that was why I was curious. This may be important as the price of the 7xxx series starts to drop as the 8xxxx units begin to become popular.

-citroja

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Hi Simon,

interesting pointer, thanks!

BTW I'm having a hard time currently with getting my "hand-tuned" stuff to a speed level that's worth mentioning :o)


Regards Hans

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More good work from our new devs. ;)

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me@rescam.org

If there anyone wants/needs to test on an nvidia 7800 series card let me know.

(still working on the card compatibility issues)

-citroja

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If there anyone wants/needs to test on an nvidia 7800 series card let me know.

(still working on the card compatibility issues)

-citroja

He,

probably my first post on this forum but since my 7800GTX isn't doing anyting at all 99% of the time, I would like to help out with testing.

Is there any info on performance after OC'ing the GPU?

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