Are you interested in OpenCL support?

[gsfare]

Hi All,

I have a working prototype for a OpenCL GPU implementation (actually based on omdcct but I'm planning to clean it up and port to cg_obup).

Let me know if you're interested and I can share my code. I'm getting approx 120k nonces per minute on my nVidia GTX 970. I've still got some work to do on it (optimisation and cleaning up) but it's a working prototype already and produces the same plots given equal parameters..

If you have any recommendations or ideas then I'm happy to discuss.

Cheers, Gareth.

[rico666]

Of course! I planned to do it myself, but am swamped, so if you make a PR it'll be most welcome.

[gsfare]

Excellent. I'll get that sorted then. Guess I need to go away and make my code nice and pretty ;-) I share your sentiment about being swamped. I will do my best to get something out there though. Code reviews are very welcome. I guess we need to look at PoC2 plots too right? Shouldn't be a huge change I think. Just a couple of lines most likely.

[rico666]

We need PoC2 too. (And the PoC2-branch needs merging too hint hint)

The wallet contains PoC1 and PoC2 OpenCL code already, maybe you can adapt that or use it to benchmark against yours.

And if yours is better, maybe we could use that in the wallet too.

So many construction sites...

[gsfare]

I just did a quick diff between master and PoC2. It doesn't look too daunting at first glance. Famous last words! I did see the OpenCL code for the wallet. It's pretty much a direct copy of the shabal256 sphlib implementation. In fact it's what I have done is also based on it but I've gone a bit further and optimised some of the macros for branching and also some memory barrier stuff. Certainly will be interesting to see any differences in performance!

What's best for the project? Create a PR from master...merge PoC2 and then add the OpenCL stuff? It's a lot of changes in one go I think so I feel it should be done separately. Also the OpenCL additions are quite independent, as in they don't really mess too much with the current implementations, rather it's a extra module for the -x parameter.

Anyway. I'll start with the OpenCL stuff. It shouldn't mess that much with the PoC2 implementation anyway and I'll add support for it at the same time.

[rico666]

If you make consecutive PRs,

• PoC2 merge
• OpenCL merge

or vice versa, it's completely sufficient. Thanks for having a look at this!

[rico666]

Any news on this?

[gsfare]

Sorry for the radio silence! Work commitments have been severely taking up my time. I won't be able to do anything for at least a month or two.

I'd be more than happy to dump you git repo though if you fancy taking a look before then. It's based on omdcct but the underlying kernel code, and usage of it, shouldn't change.

[rico666]

Yes, send the dump - let's see who has sooner time to look into it.

[gsfare]

omdcct_gpu.git.tar.gz

No probs, you should be able untar and then just "git clone" from the directory. You've got all the history then if needed.

[JohnnyFFM]

Many thanks, I'm looking into this!

[JohnnyFFM]

finally GPU support! 😃