[gmx-developers] GROMACS OpenCL on Gallium

[Vedran Miletić]

2015-11-27 20:50 GMT+01:00 Szilárd Páll <pall.szilard at gmail.com>:
> Thanks for getting back! Without CAS we won't get very far, I'm afraid. The
> kernels would need to be rewritten to dump forces to global memory and
> reduce them later which will likely completely kill performance (and it's a
> hassle to do).
>
>
>>
>> I can see what I can do, but perhaps StreamComputing guys would be the
>> ones to ask here because it is their code.
>
>
> I know the code fairly well, but I double-checked to be sure and
> (unfortunately) image support never got fixed, see:
> http://redmine.gromacs.org/projects/gromacs/repository/revisions/master/entry/src/gromacs/mdlib/nbnxn_ocl/nbnxn_ocl_data_mgmt.cpp#L208
> http://redmine.gromacs.org/projects/gromacs/repository/revisions/master/entry/src/gromacs/mdlib/nbnxn_ocl/nbnxn_ocl_data_mgmt.cpp#L423
>
> So image support is definitely not in the way of using radeonsi - and even
> if we implement it, keeping a version with simple gmem direct acesses for
> the latter parameter lookup and the analytical estimate iso tabulated Ewald
> correction (former) will always remain as an option.
>
> Cheers,
> --
> Szilárd
>

If it works, that would be uber awesome... I have to compile the stack
on radeonsi machine... I will try to do it over the weekend, don't
really want to wait next week to find out if it works or not.

Regards,
Vedran

-- 
Vedran Miletić
http://vedranmileti.ch/