将大文件写入磁盘内存不足异常

我正在尝试写入然后读取一个大型随机文件来计算磁盘速度。我尝试了多种算法，但在尝试写入 1GB 文件时不断出现输出或内存异常。这是我尝试过的一些

Method 1

   byte[] data = new byte[8192];
        Random rng = new Random();
        using (FileStream stream = File.OpenWrite(filePath))
        {
            for (int i = 0; i < fileSizeMb * 128; i++)
            {
                rng.NextBytes(data);
                stream.Write(data, 0, data.Length);
            }
        }

Method 2

const int blockSize = 1024 * 8;
            const int blocksPerMb = (1024 * 1024) / blockSize;

            int count = fileSizeMb * blocksPerMb;

            byte[] data = new byte[blockSize];
            Random rng = new Random();
            //using (FileStream stream = File.OpenWrite(filePath))
            using (StreamWriter sw1 = new StreamWriter(filePath))
            {
                // There 
                for (int i = 0; i < count; i++)
                {
                    rng.NextBytes(data);
                    sw1.BaseStream.Write(data, 0, data.Length);
                    //stream.Write(data, 0, data.Length);

                }
            }

Reading

   using (StreamReader sr = new StreamReader(filePath))
            {
                String line = sr.ReadToEnd();
            }

Method 1

        byte[] data = new byte[8192];
        Random rng = new Random();
        using (FileStream stream = File.OpenWrite(filePath))
        {
            for (int i = 0; i < fileSizeMb * 128; i++)
            {
                rng.NextBytes(data);
                stream.Write(data, 0, data.Length);
                stream.Flush(); // BEETLE JUICE
            }
        }

Method 2

        const int blockSize = 1024 * 8;
        const int blocksPerMb = (1024 * 1024) / blockSize;

        int count = fileSizeMb * blocksPerMb;

        byte[] data = new byte[blockSize];
        Random rng = new Random();
        using (StreamWriter sw1 = new StreamWriter(filePath))
        {
            // There 
            for (int i = 0; i < count; i++)
            {
                rng.NextBytes(data);
                sw1.BaseStream.Write(data, 0, data.Length);
                sw1.baseStream.Flush(); // BEETLE JUICE
            }
        }

Reading

不要将整个文件读入内存，一次只读取 4096 字节。示例代码位于http://www.csharp-examples.net/filestream-read-file/