Re: Logical replication timeout problem

Amit Kapila <amit.kapila16@gmail.com>

From: Amit Kapila <amit.kapila16@gmail.com>
To: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Cc: "wangw.fnst@fujitsu.com" <wangw.fnst@fujitsu.com>, "shiy.fnst@fujitsu.com" <shiy.fnst@fujitsu.com>, "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>, Peter Smith <smithpb2250@gmail.com>, Fabrice Chapuis <fabrice636861@gmail.com>, Euler Taveira <euler@eulerto.com>, Masahiko Sawada <sawada.mshk@gmail.com>, "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, Simon Riggs <simon.riggs@enterprisedb.com>, Petr Jelinek <petr.jelinek@enterprisedb.com>, "tanghy.fnst@fujitsu.com" <tanghy.fnst@fujitsu.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Ajin Cherian <itsajin@gmail.com>
Date: 2023-02-01T04:34:50Z
Lists: pgsql-hackers
On Tue, Jan 31, 2023 at 8:24 PM Ashutosh Bapat
<ashutosh.bapat.oss@gmail.com> wrote:
>
> On Tue, Jan 31, 2023 at 5:12 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> >
> > On Tue, Jan 31, 2023 at 5:03 PM Ashutosh Bapat
> > <ashutosh.bapat.oss@gmail.com> wrote:
> > >
> > > On Tue, Jan 31, 2023 at 4:58 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> > >
> > > > Thanks, the patch looks good to me. I have slightly adjusted one of
> > > > the comments and ran pgindent. See attached. As mentioned in the
> > > > commit message, we shouldn't backpatch this as this requires a new
> > > > callback and moreover, users can increase the wal_sender_timeout and
> > > > wal_receiver_timeout to avoid this problem. What do you think?
> > >
> > > The callback and the implementation is all in core. What's the risk
> > > you see in backpatching it?
> > >
> >
> > Because we are changing the exposed structure and which can break
> > existing extensions using it.
>
> Is that because we are adding the new member in the middle of the
> structure?
>

Not only that but this changes the size of the structure and we want
to avoid that as well in stable branches. See email [1] (you can't
change the struct size either ...). As per my understanding, our usual
practice is to not change the exposed structure's size/definition in
stable branches.


[1] - https://www.postgresql.org/message-id/2358496.1649168259%40sss.pgh.pa.us

-- 
With Regards,
Amit Kapila.



Commits

  1. Fix the logical replication timeout during large DDLs.

  2. Fix the logical replication timeout during large transactions.

  3. Rethink the delay-checkpoint-end mechanism in the back-branches.

  4. Revert "Logical decoding of sequences"

  5. Skip empty transactions for logical replication.

  6. Allow specifying column lists for logical replication

  7. Add decoding of sequences to built-in replication

  8. Fix ABI break introduced by commit 4daa140a2f.

  9. Lag tracking for logical replication