freebsd stable - Apr 2015 - protecting some processes from out-of-swap killer

On Sat, 25 Apr 2015, Baptiste Daroussin wrote:
> > However, sometimes postgres processes got killed by 'out of swap
space'.
> > I suppose the source of problem could be that VSZ size of postgres
processes
> > (8-9 G) is bigger than swap congigured (4G).
> > 
> > Is there any way to prevent this, besides reallocating space for swap?
> 
> protect(1) ?
Of course.  I really do not understand how google hides the man page from me.

Thanks, and sorry fot the noise.

-- 
Sincerely,
D.Marck                                     [DM5020, MCK-RIPE, DM3-RIPN]
[ FreeBSD committer:                                 marck at FreeBSD.org ]
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*** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck at rinet.ru ***
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On Sat, 25 Apr 2015 13:15:32 +0200, Dmitry Morozovsky <marck at rinet.ru>
wrote:
> On Sat, 25 Apr 2015, Baptiste Daroussin wrote:
>
>> > However, sometimes postgres processes got killed by 'out of
swap
>> space'.
>> > I suppose the source of problem could be that VSZ size of postgres
>> processes
>> > (8-9 G) is bigger than swap congigured (4G).
>> >
>> > Is there any way to prevent this, besides reallocating space for
swap?
>>
>> protect(1) ?
>
> Of course.  I really do not understand how google hides the man page  
> from me.
>
> Thanks, and sorry fot the noise.
>

The OS trying to kill a process is probably not what you want. So when you  
protect(1) postgres the OS will kill another process, which I hope is not  
running without reason.
My advice would be to
- or increase your swap space
- or tune postgresql to use less memory
- or limit tmpfs (tmpfs uses swap if RAM is short)
- or tune zfs to use less memory

Regards,
Ronald.