Re: [lwip-users] Increase Speed

[Kieran Mansley]

On 7 Apr 2010, at 07:15, Oscar F wrote:

> Hello everybody, i´m using lwip in AVR32 in EVK1100. 
> 
> I´m sending a big packet ( 15 Mbytes) ,

Your packets will be much smaller than that: your write of 15 Mbytes gets split 
up into lots of smaller packets that the network can handle efficiently (as you 
saw in wireshark). 

> and the time to finish the process is very high!!. In the sniffer (wireshark) 
> i saw that the packet is divided in two size 1400 and 690 i don´t remenber 
> exactly, but this order the size. 
> 
> How can i increse the speed of transmission?

Work out what is limiting the speed at the moment and improve that until it is 
no longer the bottleneck.

> should i change the file of configure lwipopt.h?  what value are typical to 
> send very fast?

lwipopts.h is where you can configure parameters to control lwIP, so this is 
the right place to be making changes.  The appropriate settings though will 
depend on your system, and I'm not familiar with your hardware.

Could you get part of a packet capture showing your transfer?  It would be 
useful to know what performance you're currently getting, and what you expect 
to get.  Is your traffic going to something on the same network or off across 
the Internet?  How much memory does your system have available, and what are 
your current lwipopts.h settings?

Thanks

Kieran