Re: pg_recvlogical prints bogus error when interrupted

At Thu, 20 Oct 2022 13:28:45 +0530, Bharath Rupireddy <bharath(dot)rupireddyforpostgres(at)gmail(dot)com> wrote in
> On Thu, Oct 20, 2022 at 3:10 AM Andres Freund <andres(at)anarazel(dot)de> wrote:
> >
> > Hi,
> >
> > While reviewing
> > https://postgr.es/m/CAD21AoBe2o2D%3Dxyycsxw2bQOD%3DzPj7ETuJ5VYGN%3DdpoTiCMRJQ%40mail.gmail.com
> > I noticed that pg_recvlogical prints
> > "pg_recvlogical: error: unexpected termination of replication stream: "
> >
> > when signalled with SIGINT/TERM.
> >
> > Oddly enough, that looks to have "always" been the case, even though clearly
> > the code tried to make provisions for a different outcome.
> >
> >
> > It looks to me like all that's needed is to gate the block printing the
> > message with an !time_to_abort.

+1

> +1. How about emitting a message like its friend pg_receivewal, like
> the attached patch?

I'm not a fan of treating SIGINT as an error in this case. It calls
prepareToTerminate() when time_to_abort and everything goes fine after
then. So I think we should do the same thing after receiving an
interrupt. This also does file-sync naturally as a part of normal
shutdown. I'm also not a fan of doing fsync at error.

> > I also then noticed that we don't fsync the output file in cases of errors -
> > that seems wrong to me? Looks to me like that block should be moved till after
> > the error:?
>
> How about something like the attached patch?

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center