cancel
Showing results for 
Search instead for 
Did you mean: 

Archives Discussions

Ignus
Journeyman III

Fusion and OpenCL

Hi!

 

Maybe I didn't search hard enough, but I haven't really found any developer documentation or guide on programming specifically AMD Fusion processors, so I would like to have some more info on that (I did find OpenCL guides, but not specific guides on optimizing for Fusion).

 

To be exact, one of my questions:

* How is the memory between CPU and GPU in Fusion handled in OpenCL? Is a copy/"upload" still done from CPU memory to "GPU memory" (when mapping/unmapping buffers for ex.), or is it possible to just pass a pointer somehow to host-allocated memory to OpenCL calls?

 

Thank you very much in advance!

 

--

Greets,

I.

 

0 Likes
7 Replies
himanshu_gautam
Grandmaster

Thanks for the suggestion. I have reported it to concerned people.

0 Likes

Hi!

 

Any news on this issue?

 

--

Greets,

I.

0 Likes

Additionally, I think it might be useful if a benchmark software was available to assess the various performance aspects of OpenCL such as:

 

- Data read/write to/from device times;
- Coalesced memory read/write times;
- Non-coalesced (random) memory read/write times;
- Atomic operation times;
- Full single-precision (and double when applicable) throughput;
- Native single-precision (and double) throughput.

 

This would bring to the scene a much better comparison tool than just run Crysis and see which GPU gets a better FPS (which, honestly, is an absolutely meaningless benchmark to non-players).

0 Likes

Originally posted by: douglas125 Additionally, I think it might be useful if a benchmark software was available to assess the various performance aspects of OpenCL such as:

 

- Data read/write to/from device times; - Coalesced memory read/write times; - Non-coalesced (random) memory read/write times; - Atomic operation times; - Full single-precision (and double when applicable) throughput; - Native single-precision (and double) throughput.

 

This would bring to the scene a much better comparison tool than just run Crysis and see which GPU gets a better FPS (which, honestly, is an absolutely meaningless benchmark to non-players).

There are several OpenCL Benchmark suites and other micro-benchmark suites (CAL/IL) available.

0 Likes

Ignus,
You want to read the documentation on 'zero-copy' with the APU's(i.e. Fusion devices).
0 Likes

Ignus,

Check out the chapter 4 of AMD APP SDK OpenCL Programming Guide.

http://developer.amd.com/gpu/amdappsdk/documentation/pages/default.aspx

0 Likes

Thanks!

Seems to be what I was looking for.

It is unfortunate however, that zero-copy buffers are only supported on WinVista/7.

Are there any plans for supporting this feature on Linux, and if so, when?

EDIT: It seems it was already answered in another thread

(Quote) "AMD releases various functionalities depending on the demands of the costomer and its priorities . Thanks for the suggestion."

Anyway, I'm looking forward to it too.

--

Greets,

I.

0 Likes