Re: PG Killed by OOM Condition

On Mon, Oct 24, 2005 at 10:20:39PM -0500, Bruno Wolff III wrote:
> On Mon, Oct 03, 2005 at 23:03:06 +1000,
>   John Hansen  wrote:
> > Good people,
> > Just had a thought!
> > Might it be worth while protecting the postmaster from an OOM Kill on
> > Linux by setting /proc/{pid}/oom_adj to -17 ?
> > (Described vaguely in mm/oom_kill.c)
> Wouldn't it be better to use sysctl to tell the kernel not to over commit
> memory in the first place?

Only if you don't have large processes in your system that fork()
frequently, pushing the reserved memory over the limit, preventing
PostgreSQL from allocating memory when it does need it, even though
copy-on-write allows plenty of memory to continue to be available -
it is just reserved... :-)

There isn't a perfect answer.

Cheers,
mark

-- 
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