Re: Really out of memory?

Ben Chobot <bench@silentmedia.com> writes:
> May 31 02:59:40 sfmelwss postgres[30103]: [1-1] ERROR:  out of memory
> May 31 02:59:40 sfmelwss postgres[30103]: [1-2] DETAIL:  Failed on request of size 16777212.

So the kernel isn't letting PG have any more memory.

> That seems pretty self-explainitory. But I'm not so sure, because SAR
> says:
> ...
> ...which indicates there was still plenty of space left in swap.

Which the kernel isn't letting us use.  Check the "ulimit" settings
that the postmaster is being started with.  On a Linux box, any of
the -d -m or -v settings might cause this.

It's possible you are running out of 32-bit address space in the backend
process, but what seems more likely is that the per-process ulimit is
unreasonably small.

            regards, tom lane