内存位置的第一次机会异常 cudaError_enum

Question

从 Visual Studio 2012 运行我的应用程序时出现此错误。 开发规范：

• 库达 5.0
• VS C++ 2012
• Quadro K4000

我看到还有其他与here、here 和here 相关的帖子，但没有一个可以很好地解决我的问题。我正在检查来自 CUDA API、CuRAND 和 CuBLAS 的所有返回代码，并且都返回成功。我查看了代码中出现问题的地方，恰好是当我为 GPU 创建一个计时器对象时。

我用的是CUDA SDK自带的定时器

struct GpuTimer{
    cudaEvent_t start;
    cudaEvent_t stop;
    GpuTimer(){
        checkCudaErr(
            cudaEventCreate(&start)
            );

        checkCudaErr(
            cudaEventCreate(&stop)
            );
    }
    ~GpuTimer(){
        checkCudaErr(
            cudaEventDestroy(start)
            );
        checkCudaErr(
            cudaEventDestroy(stop)
            );
    }
    void Start(){
        checkCudaErr(
            cudaEventRecord(start, 0)
            );
    }
    void Stop(){
        checkCudaErr(
            cudaEventRecord(stop, 0)
            );
    }
    float Elapsed(){
        float elapsed;
        checkCudaErr(
            cudaEventSynchronize(stop)
            );

        checkCudaErr(
            cudaEventElapsedTime(&elapsed, start, stop)
            );
        return elapsed;
    }
};

所以在我的主要功能中

int main(args)
{
   ...
   ...
   ...
   GpuTimer t;
   ...
   ...
}

在该行执行之后，我得到了

'App.exe' (Win32): Loaded 'C:\Windows\System32\nvcuda.dll'. Module was built without symbols.
'App.exe' (Win32): Loaded 'C:\Windows\System32\user32.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\gdi32.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\lpk.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\usp10.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\msvcrt.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\setupapi.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\cfgmgr32.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\rpcrt4.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\advapi32.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\sechost.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\oleaut32.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\ole32.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\devobj.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\shell32.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\shlwapi.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\imm32.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\msctf.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\dwmapi.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Unloaded 'C:\Windows\System32\dwmapi.dll'
'App.exe' (Win32): Loaded 'C:\Windows\System32\nvapi64.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\version.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\wintrust.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\crypt32.dll'. Cannot find or open the PDB file.
'App.exe' (Win32): Loaded 'C:\Windows\System32\msasn1.dll'. Cannot find or open the PDB file.
First-chance exception at 0x000007FEFDA29E5D in App.exe: Microsoft C++ exception: cudaError_enum at memory location 0x000000000018EA00. //Repeated 20 times at least

最后，在启动应用程序后，我在输出控制台中看到了这条消息（在 VS2012 上）

'App.exe' (Win32): Loaded 'C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v5.0\bin\cudart64_50_35.dll'. Module was built without symbols.
'App.exe' (Win32): Loaded 'C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v5.0\bin\cublas64_50_35.dll'. Module was built without symbols.
'App.exe' (Win32): Loaded 'C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v5.0\bin\curand64_50_35.dll'. Module was built without symbols.

应用程序运行良好，结果在我看来也不错，但我想知道可能导致此错误/异常的原因以及如何解决它们，或者我是否应该忽略它们。

Answer 1

您所做的观察与在 CUDA 库中正确捕获和处理的异常有关。在某些情况下，这是 CUDA GPU 操作的正常部分。正如您所观察到的，您的应用程序没有返回任何 API 错误并且可以正常运行。如果您不在可以报告此情况的 VS 环境中，则根本不会观察到此情况。

这在 CUDA 5.0 下被视为正常行为。我相信在 CUDA 5.5 中有一些消除它的尝试。您可能想尝试一下，尽管这两种方式都不是问题。

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