Search:

Type: Posts; User: Cadorino

Page 1 of 2 1 2

Search: Search took 0.00 seconds.

  1. Re: Cross-device bandwidth for discrete GPU (HD 5870)

    CL_MEM_ALLOC_HOST_PTR doesn't guarantee that the memory is allocated in any particular place. All it guarantees is that calls to clEnqueueMapBuffer() and clEnqueueMapImage() will not return...
  2. Cross-device bandwidth for discrete GPU (HD 5870)

    Hi,
    I'm testing a system equipped with a Fusion A8-3850 and an HD 5870 gpu. I was planning to test the memory access bandwidth in the following cases:

    1) The discrete GPU (HD 5870) reads from a...
  3. Replies
    2
    Views
    1,354

    Re: clEnqueueMapBuffer in discrete systems

    Nobody? :(
  4. Replies
    2
    Views
    1,354

    clEnqueueMapBuffer in discrete systems

    Hi to everybody!
    I'm performing some benchmarks to compare discrete systems (GPU separated from CPU) with APUs under various conditions/algorithms.
    At the beginning, I thought that "APUs are cool"...
  5. Re: Memory test: cpu timers vs. gpu timer sample

    I found the problem. It was simply due to an erroneout conversion between nanoseconds and milliseconds. So sorry, but it was very late :)
    Not gpu and cpu timer give me very similar results (gpu...
  6. Re: Memory test: cpu timers vs. gpu timer sample

    Additional infos...

    In case of 16 times 16 Mbytes, I get:


    Pinned -> Device
    CPU timer: 3317.04 Mbytes/s (total time: 81.06 ms)
    GPU timer: 3837185.08 Mbytes/s (total time: 0.10 ms)
  7. Memory test: cpu timers vs. gpu timer sample

    Hi,
    I'm performing some memory tests on a pc (cpu + discrete gpu) and on an apu.
    In particular, my test consists in writing Y bytes X times to find out the completion time and the average...
  8. Re: EnqueueWriteBuffer vs direct writes performance

    At least, could someone point me to a reference regarding my question? Thank you!
  9. EnqueueWriteBuffer vs direct writes performance

    Hi there,
    I'm performing some tests on an AMD fusion. I actually want to test the bandwidth of the host writing to buffers allocated in various positions (host, device, host-device accessible...
  10. Re: Performance on APU with different buffer creation strate

    I've currently installed the following driver:
    Driver Packaging Version 8.881-110728a-122938C-ATI
    Catalyst Version 11.8
    Provider ATI Technologies Inc.
    2D Driver Version 8.01.01.1178
    2D...
  11. Re: Performance on APU with different buffer creation strate

    CPU execution timings:
    http://www.gabrielecocco.it/apu/cpu_data.txt

    The kernel:
    http://www.gabrielecocco.it/apu/kernel.cl
  12. Performance on APU with different buffer creation strategies

    Hi!
    I'm testing various buffer creation streategies on an APU (acer iconia tab). The algorithm is Saxpy (vector addition), performed many times with different vector sizes. In particular, I'd like...
  13. Re: Problems in performing Saxpy with mapping/unmapping

    You are right, now it works :) Thank you thousands thousands thousands!
  14. Re: Problems in performing Saxpy with mapping/unmapping

    Or do I have to declare the buffers as local variables inside the loop (instead of simply declaring them as global and (re)allocate them each iteration)?
  15. Re: Problems in performing Saxpy with mapping/unmapping

    So my code should be ok, since I allocate both the buffers inside the for loop and therefore they are deallocated at the end of that loop, every iteration. Right?
  16. Re: Problems in performing Saxpy with mapping/unmapping

    Yup, what version are you running? Are you using the 'read' or 'map' version when you get bad results?
    [/quote]

    Hi, I'm using the map version, that is:



    bufX = cl::Buffer(
    context, ...
  17. Re: Problems in performing Saxpy with mapping/unmapping

    Visual Studio says that no operator "=" matches the operands in "bufY = NULL".
  18. Re: Problems in performing Saxpy with mapping/unmapping

    Other infos. If I try to remove free(pX) from the cleanup function (I know, it's something I shouldn't do...), the program runs fine, but the computation is wrong.
    In particular, the output of the...
  19. Re: Problems in performing Saxpy with mapping/unmapping

    The problem is that I'm using the C++ OpenCL wrapper and I can't set bufX and bufY to NULL...
  20. Re: Problems in performing Saxpy with mapping/unmapping

    Ok I think I've found the problem. The exception is raised cause this piece of code (inside cleanupHost function):



    if(pX)
    {
    free(pX);
    pX = NULL;
    }
  21. Re: Problems in performing Saxpy with mapping/unmapping

    Incredible, on my macbook it doesn't work :( I put the unmap after the calling to the function "verify", but at the second iteration I still get an heap allocation error.
    Are you sure to execute the...
  22. Re: Problems in performing Saxpy with mapping/unmapping

    I tried to put an enqueueUnmapMemObject but I continue to get an heap allocation exception. Now it is located right here:


    double gpu_time = getTimer(frequency, gpu_start);
    cout << "GPU TIME...
  23. Re: Problems in performing Saxpy with mapping/unmapping

    Do you mean clEnqueueUnmapMemObject, right? I can't find any UnmapBuffer...
  24. Re: Problems in performing Saxpy with mapping/unmapping

    Hi, I found out that the exception is thrown by the clEnqueueMap, but not at the first iteration but at the second.
    From the code i posted I excluded the outer loop that increments currNumElements...
  25. Problems in performing Saxpy with mapping/unmapping

    Hi,
    I'm trying to test an APU with different buffer creation/allocation strategies. The algorithm is the classic Saxpy (y = ax + y, where x and y are vectors).
    I encounter a problem when I try to...
Results 1 to 25 of 31
Page 1 of 2 1 2