Re: SIGSEGV from START_REPLICATION 0/XXXXXXX in XLogSendPhysical () at walsender.c:2762

Hello, Vladimir.

At Thu, 28 May 2020 11:57:23 +0300, Vladimir Sitnikov <sitnikov(dot)vladimir(at)gmail(dot)com> wrote in
> Kyotaro>It seems to me that that crash means Pgjdbc is initiating a logical
> Kyotaro>replication connection to start physical replication.
>
> Well, it used to work previously, so it might be a breaking change from the
> client/application point of view.

Mmm. It is not the proper way to use physical replication and it's
totally accidental that that worked (or even it might be a bug). The
documentation is saying as the follows, as more-or-less the same for
all versions since 9.4.

https://www.postgresql.org/docs/13/protocol-replication.html

> To initiate streaming replication, the frontend sends the replication
> parameter in the startup message. A Boolean value of true (or on, yes,
> 1) tells the backend to go into physical replication walsender mode,
> wherein a small set of replication commands, shown below, can be
> issued instead of SQL statements.
>
> Passing database as the value for the replication parameter instructs
> the backend to go into logical replication walsender mode, connecting
> to the database specified in the dbname parameter. In logical
> replication walsender mode, the replication commands shown below as
> well as normal SQL commands can be issued.

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center