Date: Mon, 28 Nov 2022 15:59:41 -0500
From: Bruce Momjian <bruce@momjian.us>
To: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Cc: Andrey Borodin <amborodin86@gmail.com>,
	Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
	Laurenz Albe <laurenz.albe@cybertec.at>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
	SATYANARAYANA NARLAPURAM <satyanarlapuram@gmail.com>
Subject: Re: An attempt to avoid
 locally-committed-but-not-replicated-to-standby-transactions in synchronous
 replication
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On Mon, Nov 28, 2022 at 12:03:06PM +0530, Bharath Rupireddy wrote:
> Thanks for verifying the behaviour. And many thanks for an off-list chat.
> 
> FWIW, I'm planning to prepare a patch as per the below idea which is
> something similar to the initial proposal in this thread. Meanwhile,
> thoughts are welcome.
> 
> 1. Disable query cancel/CTRL+C/SIGINT when a backend is waiting for
> sync replication acknowledgement.
> 2. Process proc die immediately when a backend is waiting for sync
> replication acknowledgement, as it does today, however, upon restart,
> don't open up for business (don't accept ready-only connections)
> unless the sync standbys have caught up.

You can prepare a patch, but it unlikely to get much interest until you
get agreement on what the behavior should be.  The optimal order of
developer actions is:

	Desirability -> Design -> Implement -> Test -> Review -> Commit
	https://wiki.postgresql.org/wiki/Todo#Development_Process

Telling us what other cloud vendors do is not sufficient.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

Embrace your flaws.  They make you human, rather than perfect,
which you will never be.