systat -ip, socket buffer full

[Eugene Grosbein]

24.05.2018 21:09, Ray wrote:

> when checking systat -ip I see the value for "socket buffer full" with
> values different from 0, I see 1, 2, up to 55 in one occasion.
> 
> I asked on IRC and it was mentioned I should try to up
> kern.ipc.soacceptqueue to 1024 from the default 128, but I could still see
> values over 0 in "socket buffer full".
> 
> How can I tune this buffer?
> 
> We have a lot of UDP traffic (the server is a PBX serving around 200 agents
> with avg 50 concurrent calls.

Each (udp) socket has its own limit on receiving buffer size and it is application's duty
to set its size to right value using setsockopt() function.
You should read your PBX manual on how to configure it to use larger buffers.

As last resort, you can raise sysctl kern.ipc.maxsockbuf that establishes default value
for size of such buffers that is used when application does not change defaults.
However, it may affect many applications in the system and lead to overflow of kernel memory pools
unless you know what are you doing, has plenty of free physical memory and raised kernel limits
accordingly, so better start with PBX documentation.

kern.ipc.soacceptqueue has nothing to do with "socket buffer full" problem.