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nodemcu / nodemcu-firmware

Lua based interactive firmware for ESP8266, ESP8285 and ESP32
https://nodemcu.readthedocs.io
MIT License
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net.socket cannot send big data #367

Closed drv53b6 closed 8 years ago

drv53b6 commented 9 years ago

this code realy can send only 169 lines (169 line come to distination but loop finish ok), and some time make dead loop (c is net.socket)

  c:send("<html><body>")
  for i=1,999 do
     c:send(i)
     c:send("_header<br>\r\n")
     repeat
        tmr.wdclr()
        tmr.delay(100)
     until node.heap() > 4096
  end
raz123 commented 9 years ago

You may be overflowing the send buffer, which typically has a size of 1460 bytes, IIRC. This has been discussed before. @marcoskirsch wrote a clever http server that works around this issue by yielding. Try searching.

drv53b6 commented 9 years ago

So need way to get current send buffer free size

raz123 commented 9 years ago

Not that I know of, but check the Espressif's SDK docs to make sure. Currently, the chip will perform a callback to a dedicated function when it has sent out all of its data.

PS: I do not believe that the purpose of this bug tracker is to serve as a forum.. might want to keep that in mind.

drv53b6 commented 9 years ago

raz123 - i dont now where is "forum" and how it good So no wey to send someting big? Realy need so many code for jast send big data? https://github.com/marcoskirsch/nodemcu-httpserver/blob/master/httpserver.lua

raz123 commented 9 years ago

@drv53b6, search for "1460" at esp8266.com.

drv53b6 commented 9 years ago

metod from https://github.com/marcoskirsch/nodemcu-httpserver/blob/master/httpserver.lua worck ok

marcoskirsch commented 9 years ago

nodemcu-httpserver (linked above) will send big files and it can handle multiple simultaneous requests.

drv53b6 commented 9 years ago

@marcoskirsch yous metod from https://github.com/marcoskirsch/nodemcu-httpserver/blob/master/httpserver.lua is wrong. Becose you program send more data only after TCP conformation received from destination and send bufer complete clean, see strings 326-359 at https://github.com/nodemcu/nodemcu-firmware/blob/master/app/lwip/app/espconn_tcp.c For good need function what return free space in bufer, or need make SEND calback function called after any reducing of send buffer, and will be posible send fast, without waiting for every conformation. And coroutine.yield() not worck in some impotant way: https://github.com/nodemcu/nodemcu-firmware/issues/369

marcoskirsch commented 9 years ago

What do you mean by wrong? Do you mean: a) something is incorrect in the implementation or b) it could be faster if the firmware provided a way to query the empty space in the send buffer

drv53b6 commented 9 years ago

@marcoskirsch wrong mean it the wrong way to do it

marcoskirsch commented 9 years ago

@drv53b6 what's the right way to do it?

drv53b6 commented 9 years ago

@marcoskirsch send if have space in buffer or sleep till bufer reduced

marcoskirsch commented 9 years ago

I see, but there's no way to check how much space is available in the buffer, at least today, so there's nothing we can do better until the firmware adds, it right?

drv53b6 commented 9 years ago

@marcoskirsch must use assembler inside LUA string for resolve this problem!

raz123 commented 9 years ago

@drv53b6, can you show us your better method, with code? :P

drv53b6 commented 9 years ago

@raz123 need make "net." callback for event "remove data from send,recive buffer"

TerryE commented 9 years ago

@drv53b6, this issues list is primarily for reporting bugs. If you want to learn how to use the nodeMCU Lua RTS then why not ask your Qs on the ESP8266 forum? This is a design constraint informed by the limited RAM of the ESP8266 chip, and it is quite easy to code around. I feel that this issue should be closed.

drv53b6 commented 9 years ago

@TerryE dont have way to continue sent data if have free space in send bufer (better if free space in TCP window), only posible continue send after come TCP conformation from distination

drv53b6 commented 9 years ago

if after come TCP conformarion from distination have free space in TCP windows and have free space in send bufer - execute event "can_send" for this TCP connection ok- it to difficult for this small device

TerryE commented 9 years ago

@drv53b6, I'd be pleased to help with your issue :smile: However, this isn't a bug in the firmware, so we shouldn't have this discussion here. Why not post a Q on the forum that I gave the link for and we can do it there. Also please post the necessary code fragment when you ask your Q.

drv53b6 commented 9 years ago

@TerryE no one read this stuped forum

TerryE commented 9 years ago

@drv53b6, you are trying to use tmr.delay(), so this shows to me that you don't understand a key aspect of how the nodeMCU VM and RTS works. Places like the ESP8266 and StackOverflow forums are where you get this type of explanation; not here on an issues list, so this is my last post on this here.

drv53b6 commented 9 years ago

@TerryE now im undestud

TerryE commented 8 years ago

This is an SDK limitation