Joe Lester <joe_lester(at)sweetwater(dot)com> writes:
> I tried a few different things to try to get the shmmax value to be
> something other than 4194304 (the default in /etc/rc).
> First, I restarted my mac, then, as the root user...
You can't change shmmax on-the-fly in OS X --- that's why it's set up in
/etc/rc before the system is fully operational. AFAIK the *only* way to
change these parameters is edit /etc/rc and reboot.
regards, tom lane