Unchangeable sysctl's in FreeBSD10.0 Stable

[Mateusz Guzik]

On Wed, Jun 18, 2014 at 07:17:05PM +1000, Dewayne Geraghty wrote:
> While migrating from 9.2 Stable (9.3Beta3) to 10.0Stable (r267307M) I
> noticed that some of the sysctl's that I adjust for tuning purposes
> aren't writeable, instead sysctl returns an "Invalid argument".  The two
> sysctl's of interest are:
> net.flowtable.maxflows and kern.ipc.maxsockets
> 
> Would someone advise the new way that these can be adjusted to suite the
> purpose of the servers?   There was no mention in src/UPDATING.
> 

EINVAL most likely comes from sysctl handler for given variable if it is unhappy
with new value.

net.flowtable.maxflows's will complain if you are trying to shrink it.

kern.ipc.maxsockets's will complain if the following does not hold:
                if (newmaxsockets > maxsockets &&
                    newmaxsockets <= maxfiles) {


maxfiles can be read from kern.maxfiles

-- 
Mateusz Guzik <mjguzik gmail.com>