Re: [lwip-users] [TCP raw API] Nagle + tcp_output interaction (behavior in 24 throughput tests)

[goldsimon]

vr roriz wrote:
>That's my point, I thought it would be totally unpredective. But after
>some certain amount of data is periodically queued, the RTT starts to
>go down again and the throughput is achieved. That is what I would
>like to understand.

I think tcp_output() is called every time an rx segment is processed for a pcb, 
even if it doesn't contain data but only an ack. This is to,achieve throughput 
like you want. You just cannot rely on it regarding throughput. But this could 
well explain your measurements...

>Do you think it would be a good idea to call
>tcp_output from some custom timer? (Since the poll callback has a very
>high resolution).

No. You'll just get threading problems when starting something like that...

Call tcp_output() when you want to send data. In other words, if the 
application calling your code controls send_now, make them set it to 1 for the 
last call.

Simon