No buffer space available / tcp_inpcb value

[Navdeep Parhar]

On 10/30/12 06:21, Adam Strohl wrote:
> Hey -STABLE,
>
> I've got a client who we've setup a FreeBSD cluster for with about a
> dozens servers, all behind two front end proxies/LBs/firewalls which
> also act as NAT gateways for the internal servers.
>
> On the active front end proxy we've started seeing "fatal: socket: No
> buffer space available" errors during high-peak times.   I can see in
> vmstat -z that this is what is getting denied:
>
> ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
> tcp_inpcb:              392,  32770,   19398, 13372,1449734621,6312858,   0
>
> We've got a lot of the other values bumped, and it appears to be this
> input limit that is getting hit.  There are no other non-zero FAILed
> counters except 64 and 128 buckets which I believe are normal.
>
> I cannot seem to find the sysctl (or equiv) that controls this limit
> though, or even what it is.  Anyone know?

kern.ipc.maxsockets controls this limit.  See in_pcbinfo_init() for details.

Regards,
Navdeep