Date: Mon, 28 Nov 2022 15:55:07 -0500
From: Bruce Momjian <bruce@momjian.us>
To: Andrey Borodin <amborodin86@gmail.com>
Cc: Bharath Rupireddy <bharath.rupireddyforpostgres@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 Sun, Nov 27, 2022 at 11:26:50AM -0800, Andrey Borodin wrote:
> Some funny stuff. If a user tries to cancel a non-replicated transaction
> Azure Postgres will answer: "user requested cancel while waiting for
> synchronous replication ack. The COMMIT record has already flushed to
> WAL locally and might not have been replicatead to the standby. We
> must wait here."
> AWS RDS will answer: "ignoring request to cancel wait for synchronous
> replication"
> Yandex Managed Postgres will answer: "canceling wait for synchronous
> replication due requested, but cancelation is not allowed. The
> transaction has already committed locally and might not have been
> replicated to the standby. We must wait here."
> 
> So, for many services providing Postgres as a service it's only a
> matter of wording.

Wow, you are telling me all three cloud vendors changed how query cancel
behaves on an unresponsive synchronous replica?  That is certainly a
testament that the community needs to change or at least review our
behavior.

-- 
  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.