Re: Synchronous commit behavior during network outage

st 21. 4. 2021 v 9:51 odesílatel Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at>
napsal:

> On Tue, 2021-04-20 at 18:49 +0100, Ondřej Žižka wrote:
> > tecmint=# select * from a; --> LAN on sync replica is OK
> > id
> > ----
> > 1
> > (1 row)
> >
> > tecmint=# insert into a values (2); ---> LAN on sync replica is DOWN and
> > insert is waiting. During this time kill the background process on the
> > PostgreSQL server for this session
> > WARNING: canceling the wait for synchronous replication and terminating
> > connection due to administrator command
> > DETAIL: The transaction has already committed locally, but might not
> > have been replicated to the standby.
> > server closed the connection unexpectedly
> > This probably means the server terminated abnormally
> > before or while processing the request.
> > The connection to the server was lost. Attempting reset: Succeeded.
> >
> > tecmint=# select * from a;
> > id
> > ----
> > 1
> > 2
> > (2 rows)
>
> It is well known that synchronous replication is sublect to that problem,
> since it doesn't use the two-phase commit protocol.
>
> What surprises me is that this is a warning.
> In my opinion it should be an error.
>

yes, the an error has more sense

Regards

Pavel

> Yours,
> Laurenz Albe
>
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