Re: Error reporting when hitting shared memory limits -

Peter Eisentraut <peter_e(at)gmx(dot)net> writes:
> The FreeBSD shmget(2) man page does not document this error (ENOMEM).
> However, the Linux shmget(2) page says

> ENOMEM is returned if no memory could be allocated
> for segment overhead.

> which probably means to raise SHMALL.

FWIW, HPUX 10.20 sez

[ENOMEM] A shared memory identifier and associated shared
memory segment are to be created, but the amount
of available physical memory is not sufficient to
fill the request.

which implies that you've got to buy more RAM. But experimentation
indicates that the error is actually delivered only if your request
would overrun available swap space, not physical RAM. AFAICT this
system does not even have a SHMALL parameter, though it does have a
SHMMAX limit on the size of any one shmem segment.

regards, tom lane