Information query,又稱為 device query,可以查詢設備。 以下是官方範例的檔案,由於使用到了"helper_cuda.h",所以在編譯時, 可能需要加上「-I "C:\Program Files\NVIDIA Corporation\Installer2\CUDASamples_7.5.{A212C81A-4D93-4C1C-A70E-1BBD5256D43B}\common\inc"」 (其中的路徑細節,可能需要自行替換)。:

/*
 * Copyright 1993-2015 NVIDIA Corporation.  All rights reserved.
 *
 * Please refer to the NVIDIA end user license agreement (EULA) associated
 * with this source code for terms and conditions that govern your use of
 * this software. Any use, reproduction, disclosure, or distribution of
 * this software and related documentation outside the terms of the EULA
 * is strictly prohibited.
 *
 */
/* This sample queries the properties of the CUDA devices present in the system via CUDA Runtime API. */

// Shared Utilities (QA Testing)

// std::system includes
#include <memory>
#include <iostream>

#include <cuda_runtime.h>
#include <helper_cuda.h>



int *pArgc = NULL;
char **pArgv = NULL;

#if CUDART_VERSION < 5000

// CUDA-C includes
#include <cuda.h>

// This function wraps the CUDA Driver API into a template function
template <class T>
inline void getCudaAttribute(T *attribute, CUdevice_attribute device_attribute, int device)
{
    CUresult error =    cuDeviceGetAttribute(attribute, device_attribute, device);

    if (CUDA_SUCCESS != error)
    {
        fprintf(stderr, "cuSafeCallNoSync() Driver API error = %04d from file <%s>, line %i.\n",
                error, __FILE__, __LINE__);

        // cudaDeviceReset causes the driver to clean up all state. While
        // not mandatory in normal operation, it is good practice.  It is also
        // needed to ensure correct operation when the application is being
        // profiled. Calling cudaDeviceReset causes all profile data to be
        // flushed before the application exits
        cudaDeviceReset();
        exit(EXIT_FAILURE);
    }
}

#endif /* CUDART_VERSION < 5000 */

////////////////////////////////////////////////////////////////////////////////
// Program main
////////////////////////////////////////////////////////////////////////////////
int
main(int argc, char **argv)
{
    pArgc = &argc;
    pArgv = argv;

    printf("%s Starting...\n\n", argv[0]);
    printf(" CUDA Device Query (Runtime API) version (CUDART static linking)\n\n");

    int deviceCount = 0;
    cudaError_t error_id = cudaGetDeviceCount(&deviceCount);

    if (error_id != cudaSuccess)
    {
        printf("cudaGetDeviceCount returned %d\n-> %s\n", (int)error_id, cudaGetErrorString(error_id));
        printf("Result = FAIL\n");
        exit(EXIT_FAILURE);
    }

    // This function call returns 0 if there are no CUDA capable devices.
    if (deviceCount == 0)
    {
        printf("There are no available device(s) that support CUDA\n");
    }
    else
    {
        printf("Detected %d CUDA Capable device(s)\n", deviceCount);
    }

    int dev, driverVersion = 0, runtimeVersion = 0;

    for (dev = 0; dev < deviceCount; ++dev)
    {
        cudaSetDevice(dev);
        cudaDeviceProp deviceProp;
        cudaGetDeviceProperties(&deviceProp, dev);

        printf("\nDevice %d: \"%s\"\n", dev, deviceProp.name);

        // Console log
        cudaDriverGetVersion(&driverVersion);
        cudaRuntimeGetVersion(&runtimeVersion);
        printf("  CUDA Driver Version / Runtime Version          %d.%d / %d.%d\n", driverVersion/1000, (driverVersion%100)/10, runtimeVersion/1000, (runtimeVersion%100)/10);
        printf("  CUDA Capability Major/Minor version number:    %d.%d\n", deviceProp.major, deviceProp.minor);

        char msg[256];
        SPRINTF(msg, "  Total amount of global memory:                 %.0f MBytes (%llu bytes)\n",
                (float)deviceProp.totalGlobalMem/1048576.0f, (unsigned long long) deviceProp.totalGlobalMem);
        printf("%s", msg);

        printf("  (%2d) Multiprocessors, (%3d) CUDA Cores/MP:     %d CUDA Cores\n",
               deviceProp.multiProcessorCount,
               _ConvertSMVer2Cores(deviceProp.major, deviceProp.minor),
               _ConvertSMVer2Cores(deviceProp.major, deviceProp.minor) * deviceProp.multiProcessorCount);
        printf("  GPU Max Clock rate:                            %.0f MHz (%0.2f GHz)\n", deviceProp.clockRate * 1e-3f, deviceProp.clockRate * 1e-6f);


#if CUDART_VERSION >= 5000
        // This is supported in CUDA 5.0 (runtime API device properties)
        printf("  Memory Clock rate:                             %.0f Mhz\n", deviceProp.memoryClockRate * 1e-3f);
        printf("  Memory Bus Width:                              %d-bit\n",   deviceProp.memoryBusWidth);

        if (deviceProp.l2CacheSize)
        {
            printf("  L2 Cache Size:                                 %d bytes\n", deviceProp.l2CacheSize);
        }

#else
        // This only available in CUDA 4.0-4.2 (but these were only exposed in the CUDA Driver API)
        int memoryClock;
        getCudaAttribute<int>(&memoryClock, CU_DEVICE_ATTRIBUTE_MEMORY_CLOCK_RATE, dev);
        printf("  Memory Clock rate:                             %.0f Mhz\n", memoryClock * 1e-3f);
        int memBusWidth;
        getCudaAttribute<int>(&memBusWidth, CU_DEVICE_ATTRIBUTE_GLOBAL_MEMORY_BUS_WIDTH, dev);
        printf("  Memory Bus Width:                              %d-bit\n", memBusWidth);
        int L2CacheSize;
        getCudaAttribute<int>(&L2CacheSize, CU_DEVICE_ATTRIBUTE_L2_CACHE_SIZE, dev);

        if (L2CacheSize)
        {
            printf("  L2 Cache Size:                                 %d bytes\n", L2CacheSize);
        }

#endif

        printf("  Maximum Texture Dimension Size (x,y,z)         1D=(%d), 2D=(%d, %d), 3D=(%d, %d, %d)\n",
               deviceProp.maxTexture1D   , deviceProp.maxTexture2D[0], deviceProp.maxTexture2D[1],
               deviceProp.maxTexture3D[0], deviceProp.maxTexture3D[1], deviceProp.maxTexture3D[2]);
        printf("  Maximum Layered 1D Texture Size, (num) layers  1D=(%d), %d layers\n",
               deviceProp.maxTexture1DLayered[0], deviceProp.maxTexture1DLayered[1]);
        printf("  Maximum Layered 2D Texture Size, (num) layers  2D=(%d, %d), %d layers\n",
               deviceProp.maxTexture2DLayered[0], deviceProp.maxTexture2DLayered[1], deviceProp.maxTexture2DLayered[2]);


        printf("  Total amount of constant memory:               %lu bytes\n", deviceProp.totalConstMem);
        printf("  Total amount of shared memory per block:       %lu bytes\n", deviceProp.sharedMemPerBlock);
        printf("  Total number of registers available per block: %d\n", deviceProp.regsPerBlock);
        printf("  Warp size:                                     %d\n", deviceProp.warpSize);
        printf("  Maximum number of threads per multiprocessor:  %d\n", deviceProp.maxThreadsPerMultiProcessor);
        printf("  Maximum number of threads per block:           %d\n", deviceProp.maxThreadsPerBlock);
        printf("  Max dimension size of a thread block (x,y,z): (%d, %d, %d)\n",
               deviceProp.maxThreadsDim[0],
               deviceProp.maxThreadsDim[1],
               deviceProp.maxThreadsDim[2]);
        printf("  Max dimension size of a grid size    (x,y,z): (%d, %d, %d)\n",
               deviceProp.maxGridSize[0],
               deviceProp.maxGridSize[1],
               deviceProp.maxGridSize[2]);
        printf("  Maximum memory pitch:                          %lu bytes\n", deviceProp.memPitch);
        printf("  Texture alignment:                             %lu bytes\n", deviceProp.textureAlignment);
        printf("  Concurrent copy and kernel execution:          %s with %d copy engine(s)\n", (deviceProp.deviceOverlap ? "Yes" : "No"), deviceProp.asyncEngineCount);
        printf("  Run time limit on kernels:                     %s\n", deviceProp.kernelExecTimeoutEnabled ? "Yes" : "No");
        printf("  Integrated GPU sharing Host Memory:            %s\n", deviceProp.integrated ? "Yes" : "No");
        printf("  Support host page-locked memory mapping:       %s\n", deviceProp.canMapHostMemory ? "Yes" : "No");
        printf("  Alignment requirement for Surfaces:            %s\n", deviceProp.surfaceAlignment ? "Yes" : "No");
        printf("  Device has ECC support:                        %s\n", deviceProp.ECCEnabled ? "Enabled" : "Disabled");
#if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64)
        printf("  CUDA Device Driver Mode (TCC or WDDM):         %s\n", deviceProp.tccDriver ? "TCC (Tesla Compute Cluster Driver)" : "WDDM (Windows Display Driver Model)");
#endif
        printf("  Device supports Unified Addressing (UVA):      %s\n", deviceProp.unifiedAddressing ? "Yes" : "No");
        printf("  Device PCI Domain ID / Bus ID / location ID:   %d / %d / %d\n", deviceProp.pciDomainID, deviceProp.pciBusID, deviceProp.pciDeviceID);

        const char *sComputeMode[] =
        {
            "Default (multiple host threads can use ::cudaSetDevice() with device simultaneously)",
            "Exclusive (only one host thread in one process is able to use ::cudaSetDevice() with this device)",
            "Prohibited (no host thread can use ::cudaSetDevice() with this device)",
            "Exclusive Process (many threads in one process is able to use ::cudaSetDevice() with this device)",
            "Unknown",
            NULL
        };
        printf("  Compute Mode:\n");
        printf("     < %s >\n", sComputeMode[deviceProp.computeMode]);
    }

    // If there are 2 or more GPUs, query to determine whether RDMA is supported
    if (deviceCount >= 2)
    {
        cudaDeviceProp prop[64];
        int gpuid[64]; // we want to find the first two GPUs that can support P2P
        int gpu_p2p_count = 0;

        for (int i=0; i < deviceCount; i++)
        {
            checkCudaErrors(cudaGetDeviceProperties(&prop[i], i));

            // Only boards based on Fermi or later can support P2P
            if ((prop[i].major >= 2)
#if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64)
                // on Windows (64-bit), the Tesla Compute Cluster driver for windows must be enabled to support this
                && prop[i].tccDriver
#endif
               )
            {
                // This is an array of P2P capable GPUs
                gpuid[gpu_p2p_count++] = i;
            }
        }

        // Show all the combinations of support P2P GPUs
        int can_access_peer;

        if (gpu_p2p_count >= 2)
        {
            for (int i = 0; i < gpu_p2p_count; i++)
            {
                for (int j = 0; j < gpu_p2p_count; j++)
                {
                    if (gpuid[i] == gpuid[j])
                    {
                        continue;
                    }
                    checkCudaErrors(cudaDeviceCanAccessPeer(&can_access_peer, gpuid[i], gpuid[j]));
                        printf("> Peer access from %s (GPU%d) -> %s (GPU%d) : %s\n", prop[gpuid[i]].name, gpuid[i],
                           prop[gpuid[j]].name, gpuid[j] ,
                           can_access_peer ? "Yes" : "No");
                }
            }
        }
    }

    // csv masterlog info
    // *****************************
    // exe and CUDA driver name
    printf("\n");
    std::string sProfileString = "deviceQuery, CUDA Driver = CUDART";
    char cTemp[16];

    // driver version
    sProfileString += ", CUDA Driver Version = ";
#if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64)
    sprintf_s(cTemp, 10, "%d.%d", driverVersion/1000, (driverVersion%100)/10);
#else
    sprintf(cTemp, "%d.%d", driverVersion/1000, (driverVersion%100)/10);
#endif
    sProfileString +=  cTemp;

    // Runtime version
    sProfileString += ", CUDA Runtime Version = ";
#if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64)
    sprintf_s(cTemp, 10, "%d.%d", runtimeVersion/1000, (runtimeVersion%100)/10);
#else
    sprintf(cTemp, "%d.%d", runtimeVersion/1000, (runtimeVersion%100)/10);
#endif
    sProfileString +=  cTemp;

    // Device count
    sProfileString += ", NumDevs = ";
#if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64)
    sprintf_s(cTemp, 10, "%d", deviceCount);
#else
    sprintf(cTemp, "%d", deviceCount);
#endif
    sProfileString += cTemp;

    // Print Out all device Names
    for (dev = 0; dev < deviceCount; ++dev)
    {
#if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64)
        sprintf_s(cTemp, 13, ", Device%d = ", dev);
#else
        sprintf(cTemp, ", Device%d = ", dev);
#endif
        cudaDeviceProp deviceProp;
        cudaGetDeviceProperties(&deviceProp, dev);
        sProfileString += cTemp;
        sProfileString += deviceProp.name;
    }

    sProfileString += "\n";
    printf("%s", sProfileString.c_str());

    printf("Result = PASS\n");

    // finish
    // cudaDeviceReset causes the driver to clean up all state. While
    // not mandatory in normal operation, it is good practice.  It is also
    // needed to ensure correct operation when the application is being
    // profiled. Calling cudaDeviceReset causes all profile data to be
    // flushed before the application exits
    cudaDeviceReset();
    exit(EXIT_SUCCESS);
}

以 GTX 740M 為例,此程式的主要輸出如下:

Device 0: "GeForce GT 740M"
  CUDA Driver Version / Runtime Version          7.5 / 7.5
  CUDA Capability Major/Minor version number:    3.5
  Total amount of global memory:                 2048 MBytes (2147483648 bytes)
  ( 2) Multiprocessors, (192) CUDA Cores/MP:     384 CUDA Cores
  GPU Max Clock rate:                            1033 MHz (1.03 GHz)
  Memory Clock rate:                             800 Mhz
  Memory Bus Width:                              64-bit
  L2 Cache Size:                                 524288 bytes
  Maximum Texture Dimension Size (x,y,z)         1D=(65536), 2D=(65536, 65536), 3D=(4096, 4096, 4096)
  Maximum Layered 1D Texture Size, (num) layers  1D=(16384), 2048 layers
  Maximum Layered 2D Texture Size, (num) layers  2D=(16384, 16384), 2048 layers
  Total amount of constant memory:               65536 bytes
  Total amount of shared memory per block:       49152 bytes
  Total number of registers available per block: 65536
  Warp size:                                     32
  Maximum number of threads per multiprocessor:  2048
  Maximum number of threads per block:           1024
  Max dimension size of a thread block (x,y,z): (1024, 1024, 64)
  Max dimension size of a grid size    (x,y,z): (2147483647, 65535, 65535)
  Maximum memory pitch:                          2147483647 bytes
  Texture alignment:                             512 bytes
  Concurrent copy and kernel execution:          Yes with 1 copy engine(s)
  Run time limit on kernels:                     No
  Integrated GPU sharing Host Memory:            No
  Support host page-locked memory mapping:       Yes
  Alignment requirement for Surfaces:            Yes
  Device has ECC support:                        Disabled
  CUDA Device Driver Mode (TCC or WDDM):         WDDM (Windows Display Driver Model)
  Device supports Unified Addressing (UVA):      Yes
  Device PCI Domain ID / Bus ID / location ID:   0 / 1 / 0
  Compute Mode:
     < Default (multiple host threads can use ::cudaSetDevice() with device simultaneously) >