Re: Small fixes needed by high-availability tools
Amit Kapila <amit.kapila16@gmail.com>
From: Amit Kapila <amit.kapila16@gmail.com>
To: Mihail Nikalayeu <mihailnikalayeu@gmail.com>
Cc: Ants Aasma <ants.aasma@cybertec.at>,
Andrey Borodin <x4mmm@yandex-team.ru>, Matthias van de Meent <boekewurm+postgres@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2025-05-14T09:33:33Z
Lists: pgsql-hackers
On Wed, May 14, 2025 at 2:15 AM Mihail Nikalayeu <mihailnikalayeu@gmail.com> wrote: > > > One idea to solve this problem could be that whenever we cancel > > sync_rep_wait, we set some system-wide flag that indicates that any > > new transaction must ensure that all the current data is replicated to > > the synchronous standby. Once we ensure that we have waited for > > pending transactions to replicate, we can toggle back that system-wide > > flag. Now, if the system restarts for any reason during such a wait, > > we can use your idea to disallow new connections until the standby > > quorum is established. > > It might not necessarily be a flag—it could be some LSN value instead. > Also, it's not just about a "new transaction," but about any new > snapshot that could see data not yet replicated to the synchronous > standby. > Sounds reasonable to me. Let us see what others think about it. -- With Regards, Amit Kapila.