Re: [lwip-users] lwIP 1.4.1 stable tcp connection stall

[Bill Auerbach]

Hi Simon,

 

I see a zero window persist timer bugfix entry in 1.4.1.

 

I can ping-pong 2.0.2 and 1.4.1 and make the error come and go. At first on the NIOS II but being slower and harder to debug I just got the PowerPC converted to 2.0.2 and it’s working there too (as expected).  The PowerPC allows me faster debugging and much more horsepower to output debug information.  And I can get the debug output in Telnet.  I can debug some, yes, but I’m no expert on this part of lwIP or TCP.  So I need help in what information is best to gather. I can pause when the sending stops and get to these variables.  Would output from LWIP_DEBUG_ONs (whichever ones are pertinent) show you anything about what’s happening?

 

Thank you for replying. Your dedication to this product is evident by your interest in knowing what fixed something in an older version. Due to time I may have to push a 2.0.2-based release out.  Do to the seriousness I could see you pushing a DIY code change for users to update 1.4.1 code to reduce the concern of a major update.  It got some nervous here when I said there were probably a hundred changes in 2.x. But I’ve already run a test with 3 devices using 30M packets and I see no differences from 1.4.1. I will run overnight as well.

 

Bill

 

From: lwip-users [mailto:lwip-users-bounces+address@hidden On Behalf Of goldsimon
Sent: Wednesday, August 09, 2017 10:45 AM
To: Mailing list for lwIP users
Subject: Re: [lwip-users] lwIP 1.4.1 stable tcp connection stall

 

Hey Bill,

Great to hear 2.0.2 fixes this. I'm a bit lost thinking about a bug fix. We had some since then I guess, and I would have to dig through the log myself.
However, the most obvious would be a zero window where the persist timer doesn't start or somehow doesn't work correctly.

Are you able to reproduce this now? Can you debug it? Would you need help in debugging?

I'm not at my PC very often right now, but I'll see if I find something. Maybe you can dump the PCB in question once it stops plus lwip_stats, that could help finding the issue.

Simon