Re: [lwip-users] very poor performance of httpd

[Mário Luzeiro]

Hi Felix,

I had similar issues but using TLS
https://lists.nongnu.org/archive/html/lwip-users/2020-05/msg00006.html

I experience the same: some requests are very quick and others take seconds.
..but didn't found a solution yet.

I will follow this thread in case someone comes with more suggestions.

I suggest you can start trying to increase MEMP_NUM_TCP_PCB to the double
I think play with smaller values in TCP_MSS and/or TCP_WND could help.. but not 
sure...

Mario

________________________________________
From: lwip-users <lwip-users-bounces+mrluzeiro=ua.pt@nongnu.org> on behalf of 
Felix Frey <frey@stettbacher.ch>
Sent: 17 August 2020 14:40
To: lwip-users@nongnu.org
Subject: [lwip-users] very poor performance of httpd

Hi,

I've running an application on a STM32F429 using LwIP 2.0.3 and it's httpd.
Basically it works fine, however the performance of the httpd is very poor.

When the browser does a http request for a total of five files (statically 
linked)
with a total amount of 40kB, it takes about 5sec to complete the request.
It seems like the httpd gets stalled.
In the log I can see several of the entrys below:
-----
00006.560: http_poll: pcb=0x2000d7b8 hs=0x2000db08 pcb_state=ESTABLISHED
00006.560: http_poll: try to send more data
00006.560: http_send: hs=0x2000db08 pcb=0x2000d7b8 left=22030
00006.560: Trying to send 0 bytes
00006.560: Sent 0 bytes
00006.560: send_data end.
00006.560: tcp_output
-----
This is repeated every 500ms for about 2sec until sending moves on.
It looks like it simply doesn't anything during this time. Why??

My memory settings are:
#define MEM_LIBC_MALLOC 1
#define MEMP_NUM_TCP_PCB 8
#define MEMP_NUM_PBUF 32
#define TCP_MSS 1460
#define TCP_WND 2920

I've already played with configuration settings, however, it didn't change a 
lot.
Can anybody explain this behaviour or even help to improve it?

Thanks in advance.
Felix

_______________________________________________
lwip-users mailing list
lwip-users@nongnu.org
https://lists.nongnu.org/mailman/listinfo/lwip-users