请教一下，如何提高RTT+LWIP的网络吞吐能力？

发布于 2012-03-02 10:54:25 浏览：4897 订阅该版

用BSP里的STM32F107例子，增加TCPECHO线程并挂接netio进行测试；
netio的测试结果如下：
D:iperf-2.0.5>win32-i386 -t 192.168.8.45

TCP connection established.
Packet size  1k bytes:  1097 KByte/s Tx,  4304 Byte/s Rx.
Packet size  2k bytes:  1094 KByte/s Tx,  488 KByte/s Rx.
Packet size  4k bytes:  1102 KByte/s Tx,  916 KByte/s Rx.
Packet size  8k bytes:  1100 KByte/s Tx,  864 KByte/s Rx.
Packet size 16k bytes:  1102 KByte/s Tx,  904 KByte/s Rx.
Packet size 32k bytes:  1104 KByte/s Tx,  896 KByte/s Rx.
Done.

TCPECHO使用ipref进行测试，结果如下：
D:iperf-2.0.5>iperf -c 192.168.8.45 --port 8000
------------------------------------------------------------
Client connecting to 192.168.8.45, TCP port 8000
TCP window size: 64.0 KByte (default)
------------------------------------------------------------
[  3] local 192.168.8.161 port 1700 connected with 192.168.8.45 port 8000
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-25.0 sec   192 KBytes  63.0 Kbits/sec

TCPECHO的测试代码如下：
```
char buf[1024];

void rt_tcp_echo_thread_entry(void *parameter)
{
	int ret=0;
	int local_socket,echo_socket;
    struct sockaddr_in	echo_addr,from;
	socklen_t   addr_len = sizeof(struct sockaddr_in);

echo_addr.sin_family = AF_INET;
    echo_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    echo_addr.sin_port = htons(8000);
	rt_kprintf("Creat Echo socket thread start!
");
	while(1)
	{
		local_socket = socket(AF_INET, SOCK_STREAM,IPPROTO_TCP);
		if(INVALID_SOCKET == local_socket)
		{
			rt_kprintf("Creat Echo socket failed!
");
			rt_thread_delay(100);
			continue;
		}
		ret = bind(local_socket,(struct sockaddr*)&echo_addr, addr_len)	;
		if (SOCKET_ERROR == ret) 
	    {
	        closesocket(local_socket);
	        echo_socket = INVALID_SOCKET;
	        rt_kprintf("local_socket bind port failed with %d
",ret);
	        rt_thread_delay(100);
			continue ;
	    }
		ret = listen(local_socket,5);
		if (SOCKET_ERROR == ret) 
	    {
	        closesocket(local_socket);
	        echo_socket = INVALID_SOCKET;
	        rt_kprintf("local_socket listen port failed with %d
",ret);
	        rt_thread_delay(100);
			continue ;
	    }
		while(1)
		{
			echo_socket = accept(local_socket,(struct sockaddr*)&from,&addr_len);
			if(INVALID_SOCKET == echo_socket)
			{
				rt_thread_delay(100);
				continue;
			}
			while(1)
			{
				ret=recv(echo_socket, buf, sizeof(buf), 0);
				if(ret > 0)
				{
					send(echo_socket,buf,ret,0);
				}
				else
				{
					closesocket(echo_socket);
					break;
				}
			}
		}
	}
}

线程挂载部分：

echo_thread = rt_thread_create("tcpecho",
                                   rt_tcp_echo_thread_entry, RT_NULL,
                                   2048, 3, 1);
	if(RT_NULL == echo_thread)
	{
		rt_kprintf("creat tcp echo failed
");
	}
	else
	{
		rt_thread_startup(echo_thread);
	}
```

与我之前测试的另外一块芯片，没有用操作系统，相比之下，差距太大了。
![1.jpg](/uploads/1149_943f9b1ad0e8b4c96790e9a534ec3363.jpg)

**请问要想提高速率，该从哪些方面下手？ 谢谢。**