Re: [lwip-users] TCP Dup ACKs and TCP Window full
I've been lurking in listen-only mode since I don't know the netconn API. The PC is sending as fast as it can, but the device is synchronized to the storage speed, so incoming data needs to be buffered and eventually slowed down, and that is what TCP tries to do. However, your packet loss is a bigger problem (I didn't look into that, stopped at the buffering stuff), which you just solved. You can help TCP by providing a bigger intermediate buffer, but it will only delay the real issue if the file is long enough. Please don't take this as thread-hijacking: On the RAW API I would delay my calls to tcp_recved() forcing TCP to delay ACKs (perhaps this has some other issues ?). Is there any mechanism for throttling in the netconn API ? Cheers. ___ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users
Re: [lwip-users] TCP Dup ACKs and TCP Window full
Thanks, you could have even left it in german :) It works now with an increased pool size. #define PBUF_POOL_SIZE 1024 I was actually getting memory errors now with Lwip 2.0.3, where I was not getting them with 1.4.1, although the settings were the same. I can only recommend to use Lwip 2 instead of 1.4. I get occasional Zero Window/Window full, but no packets are dropped anymore. Thanks again, Adrian Von: lwip-users Im Auftrag von goldsi...@gmx.de Gesendet: Tuesday, April 10, 2018 10:11 PM An: Mailing list for lwIP users Betreff: Re: [lwip-users] TCP Dup ACKs and TCP Window full On 10.04.2018 22:04, Adrian Figueroa wrote: Ok, I do not usually take captures, so I did not know I can shorten them. I will try next time. You can. Check the options you have in "File" --> "export special packets..." (translated from my german GUI). Simon smime.p7s Description: S/MIME cryptographic signature ___ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users
Re: [lwip-users] TCP Dup ACKs and TCP Window full
On 10.04.2018 22:04, Adrian Figueroa wrote: Ok, I do not usually take captures, so I did not know I can shorten them. I will try next time. You can. Check the options you have in "File" --> "export special packets..." (translated from my german GUI). Simon ___ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users
Re: [lwip-users] TCP Dup ACKs and TCP Window full
Ok, I do not usually take captures, so I did not know I can shorten them. I will try next time. I will check memory settings and reevaluate if there are errors. Adrian Von: lwip-users Im Auftrag von goldsi...@gmx.de Gesendet: Dienstag, 10. April 2018 21:43 An: Mailing list for lwIP users Betreff: Re: [lwip-users] TCP Dup ACKs and TCP Window full On 10.04.2018 16:53, Adrian Figueroa wrote: [..] I had to upload them here, because they were rejected as an attachment due to size. That's not really true. You had to upload the files because noone wants to load ~300 kByte into their mail inbox just because you're too lazy to strip down the pcap to what's necessary to show your problem ;-) Uploading them to some weird 3rd party platform is not really a nice response to that limit... Simon ___ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users
Re: [lwip-users] TCP Dup ACKs and TCP Window full
On 10.04.2018 16:53, Adrian Figueroa wrote: [..] I had to upload them here, because they were rejected as an attachment due to size. That's not really true. You had to upload the files because noone wants to load ~300 kByte into their mail inbox just because you're too lazy to strip down the pcap to what's necessary to show your problem ;-) Uploading them to some weird 3rd party platform is not really a nice response to that limit... Simon ___ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users
Re: [lwip-users] TCP Dup ACKs and TCP Window full
On 10.04.2018 16:53, Adrian Figueroa wrote: [..]I think, this problem is not caused by Lwip itself but probably a configuration error or some buffer that runs full. Maybe even a speed issue of the processor. I think it's a processor speed issue. Lost packets could be an lwIP configuration issue (have a look at 'lwip_stats.mem' and 'lwip_stats.memp' to check the 'err' counters). But 'TCP window full' just means the PC sends faster than the device can handle. I managed to run iPerf with ~100 mbit/s on an STM32 (with STM HAL drivers fixed/improved by myself), but I don't remember the CPU speed... It could also be a driver issue, but I think the ChibiOS drivers are better than the STM HAL ones.. Simon ___ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users
Re: [lwip-users] TCP Dup ACKs and TCP Window full
On 06.04.2018 15:30, Adrian Figueroa wrote: I am writing a bootloader application that receives data over ethernet for flashing the processor it runs on. This is implemented on an STM32F746 running the ChibiOS-RTOS and the HAL drivers that come with it. Consequently, the netconn-api is used. I run Lwip 1.4.1, because Lwip 2.X was not yet ported to ChibiOS and I cannot to do it myself. Lwip is used to implement a simple TCP server. A python TCP client connects to it and sends a chunk of data (around 200k). I moved Lwip pools and heap to external SDRAM, so I can store large amounts of packets without discarding them. First, the TCP server thread waits for an incoming connection with “netconn_accept()”. Find this in “server.c”, attached to this mail. There is also a “helper” thread that cleans things up after a connection was closed (dynamic threads). After “netconn_accept()”, the netconn is handed over to a thread that receives data. Find the receiver functionality in “receiver.c”. The receiver constantly calls netconn_recv(), until the connection is closed. A netbuf is filled each time and chained to the previous netbuf. I also have an evaluation thread that works on the received netbufs, but it does not do anything at the moment. In the end, I have a long netbuf chain in memory, ready for evaluation. The problem is that I lose some of the packets in the process. Find the dump from Wireshark attached. My lwipopts.h is also included in the mail. I chose very generous amounts of storage for all pools, because I have 32 MB of SDRAM available. I get no errors at all in lwip_stats. Do you have any suggestions? Are you aware that you seem to be using TCP segmentation offloading on your windows network card? The wireshark trace shows TCP segments with 5840 bytes although MSS is advertised as 1460 by lwIP. If you want (us) to debug network problems using wireshark, please ensure you change the driver settings to make wireshark let you see what's on the cable! Simon ___ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users
