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我的代码遇到了一些奇怪的行为，我用这些行为将文件流式传输到我的客户。我有一个用作文件存储的 mssql 服务器，其中包含通过 UNC 路径访问的文件。

在我的网络服务器上，我运行了一些 .net 代码，用于将文件（在本例中为图片和缩略图）流式传输到我的客户。

我的代码有效，但我在初始文件请求时遇到了约 12 秒的持续延迟。当我发出初始请求时，服务器唤醒并突然变得响应，只是在一段时间后回退到相同的行为。

起初我以为这是我的代码，但从我在服务器活动日志中看到的内容来看，没有资源密集型代码正在运行。我的理论是，在每次调用服务器时，必须首先安装路径，这就是导致延迟的原因。然后它将在一段时间后卸载，并且必须重新安装。

作为参考，我发布了我的代码（也许我只是看不到问题）：

public async static Task StreamFileAsync(HttpContext context, FileInfo fileInfo)
{
        //This controls how many bytes to read at a time and send to the client
        int bytesToRead = 512 * 1024; // 512KB

        // Buffer to read bytes in chunk size specified above
        byte[] buffer = new Byte[bytesToRead];

        // Clear the current response content/headers
        context.Response.Clear();
        context.Response.ClearHeaders();

        //Indicate the type of data being sent
        context.Response.ContentType = FileTools.GetMimeType(fileInfo.Extension);

        //Name the file
        context.Response.AddHeader("Content-Disposition", "filename=\"" + fileInfo.Name + "\"");
        context.Response.AddHeader("Content-Length", fileInfo.Length.ToString());

        // Open the file
        using (var stream = fileInfo.OpenRead())
        {
            // The number of bytes read
            int length;
            do
            {
                // Verify that the client is connected
                if (context.Response.IsClientConnected)
                {
                    // Read data into the buffer
                    length = await stream.ReadAsync(buffer, 0, bytesToRead);

                    // and write it out to the response's output stream
                    await context.Response.OutputStream.WriteAsync(buffer, 0, length);

                    try
                    {
                        // Flush the data
                        context.Response.Flush();
                    }
                    catch (HttpException)
                    {
                        // Cancel the download if a HttpException happens
                        // (ie. the client has disconnected by we tried to send some data)
                        length = -1;
                    }

                    //Clear the buffer
                    buffer = new Byte[bytesToRead];
                }
                else
                {
                    // Cancel the download if client has disconnected
                    length = -1;
                }
            } while (length > 0); //Repeat until no data is read
        }

        // Tell the response not to send any more content to the client
        context.Response.SuppressContent = true;

        // Tell the application to skip to the EndRequest event in the HTTP pipeline
        context.ApplicationInstance.CompleteRequest();
    }

如果有人能对这个问题有所了解，我将不胜感激！

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