Re: No buffer space available

[Joerg Sonnenberger <joerg%britannica.bec.de@localhost>]

On Mon, Sep 01, 2014 at 08:08:25PM +0200, Tom Ivar Helbekkmo wrote:
> Michael van Elst <mlelstv%serpens.de@localhost> writes:
> 
> > This doesn't necessarily mean that the buffer space is too small. It
> > often also means that you try to send data faster than possible
> > through the particular hardware.
> > [...]
> > It could be that the kernel address space is exhausted but this
> > shouldn't really happen with default settings.
> 
> This rung a bell, and got me started looking for things that might be
> other than default.  I found some stuff in /etc/sysctl.conf picked up
> from https://wiki.netbsd.org/tutorials/tuning_netbsd_for_performance/
> a long time ago, when the machine had quite different tasks:
> 
> net.inet.tcp.recvbuf_auto=1
> net.inet.tcp.sendbuf_auto=1
> net.inet.tcp.sendbuf_max=16777216
> net.inet.tcp.recvbuf_max=16777216
> vm.filemax=20
> 
> Reverting those to their defaults solved my problem.

Note that scaling up the send/recv buf alone won't help without also
raising kern.somax.

Joerg