Re: PSA: Systemd will kill PostgreSQL

On Tue, Aug 16, 2016 at 5:24 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:

> Magnus Hagander <magnus@hagander.net> writes:
> > On Aug 16, 2016 5:11 PM, "Tom Lane" <tgl@sss.pgh.pa.us> wrote:
> >> Dunno, it was still working the last time I used Fedora for anything
> much.
> >> Admittedly, that was about three years ago.  But the issue would still
> >> arise if you prefer "pg_ctl start".
>
> > There are two independent changes AFAIK. One is that whenever a user that
> > logged in interactively logs out all their processes are killed,
> regardless
> > of nohup. The other one is the one about shared memory mentioned here.
> They
> > will both independently kill postgres sessions launched manually. Or with
> > pg_ctl.
>
> Not sure I believe that --- the cases that have been reported to us
> involved postgres processes that were still alive but had had their
> SysV semaphore sets deleted out from under them.  Likely the SysV
> shmem segments too, but that wouldn't cause any observable effects
> for the running cluster.  (It *would* risk breaking the interlock
> against starting a new postmaster, I fear.)
>
> It might be that both behaviors exist now but more people know about
> how to turn off the killing-processes one.
>
>
Yes, I think it's the second. See for example
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=825394. You can configure
KillUserProcesses=no in logind.conf to get rid of it (that bug discusses
the debian default behaviour).



-- 
 Magnus Hagander
 Me: http://www.hagander.net/
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