RE: [lwip-users] tcp_write() errors on snd_queuelen

[Tim Lambrix]

I want to thank you all for your help and information.  It has certainly been 
appreciated is solving this problem I have had for quite a while.  

A few more questions: What are the performance tradeoffs of a larger TCP_MSS 
versus a smaller one when calling tcp_write with a typical 40 byte write?  
Obviously, I want to keep the memory requirements as small as possible but be 
able to handle the load in (practically) any network. 

I see the default for MEM_SIZE is only 1600.  I have mine set to 22K but is 
this really necessary?  How should one go about picking reasonable values for 
memory and TCP requirements that are sufficient?  Is there a formula or 
calculation for any of these based on the frequency that tcp_write is called?

While running yesterday on with the TCP_QLEN_DEBUG enabled, I saw two times 
that over a second went by that no tcp_recieve was called and therefore the 
snd_queuelen value reached the TCP_SND_QUEUELEN limit I have set in the options 
file.  Is this typical and what approach would you recommend such that this 
doesn't happen - keep growing the TCP_SND_QUEUELEN or is there something else 
not configured correctly (perhaps the TCP_WND not being at least 2* or 4* the 
TCP_MSS)?

_______________________________________________
lwip-users mailing list
address@hidden
http://lists.nongnu.org/mailman/listinfo/lwip-users