sonewconn: pcb 0xc442c9c0: Listen queue overflow: 193 already in queue awaiting acceptance (19 occurrences)

[Sylvain]

Hello,

I have many messages like this one:
sonewconn: pcb 0xc442c9c0: Listen queue overflow: 193 already in queue awaiting acceptance (18 occurrences)

in my dmesg log, on a raspberry pi 2.

I’m pretty sure the culprit is my bittorrent client. 

I suppose I can 
a) tune my transmission client not to accept so many connections
b) tune my kernel to have a bigger listen queue

I’m writing here in case someone could point for me the right sysctl I need to tune for case b)

Thanks!
Sylvain