Re: [lwip-users] TCP Config in lwIP

[Noam Weissman]

Hi,

 

Why do you need so much RAM for MEM_SIZE ?

 

I think it is not a problem of RAM it is something in you code that does not

handle properly the data. You are maybe not freeing buffers properly ?

 

Do you use LwIP in RAW mode or in Socket mode ?

 

BR,

Noam.

 

From: lwip-users-bounces+address@hidden [mailto:lwip-users-bounces+address@hidden On Behalf Of D??ng Anh S?n
Sent: Tuesday, March 01, 2016 9:03 AM
To: address@hidden
Subject: [lwip-users] TCP Config in lwIP

 

Hello,

I'm working on lwIP for sending data for raspberry device to windows server. I use config below:

 

#define MEM_SIZE (1 * 1024 * 1024) 

#define PBUF_POOL_SIZE (1024 * 4) 

#undef PBUF_POOL_BUFSIZE 

#define MEMP_NUM_TCP_PCB 128 

#define MEMP_NUM_NETCONN 128 

#define TCP_QUEUE_OOSEQ 1 

#define TCP_MSS 1460 

#define TCP_SND_BUF TCP_WND 

#define TCP_SND_QUEUELEN (4 * TCP_SND_BUF/TCP_MSS) 

#define TCP_WND 8 * TCP_MSS 

 

But send speed ~20 MB/s and after about 10-20 seconds, i can't send data any more and server send back many "dup ack" packets.

 

Please suggest any good config for using tcp with lwIP.

 

Regards,

Sol