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Date: Sun, 14 Sep 2014 21:27:35 +0200
From: Bram Van Steenlandt <bram@diomedia.be>
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Subject: Listen queue guestion
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Hi,

I'm porting an plc automation system to freebsd and while doing so I got 
errors like these:
sonewconn: pcb 0xfffff8000cecc870: Listen queue overflow: 76 already in 
queue awaiting acceptance

With the help of netstat I've found the problem, 2 programs communicate 
with ipc file like sockets and the "client" was connecting too fast (it 
was connecting and disconnecting in a small for loop).

Still, on linux this worked and there will be cases where I may bump in 
to this limit again (a lot of different programs communicate with one 
master program over ipc).

I've found kern.ipc.somaxconn but this seems to be only for TCP connections.

Is there a sysctl or kernel parameter that allows me to set this queue a 
bit larger ?

Thx
Bram