Message-ID: <d8f1f66dfe845a7d18eba7b6e5a27b2f1a887b57.camel@j-davis.com>
Subject: Re: Minimal logical decoding on standbys
From: Jeff Davis <pgsql@j-davis.com>
To: Andres Freund <andres@anarazel.de>
Cc: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>, Robert Haas
 <robertmhaas@gmail.com>, Thomas Munro <thomas.munro@gmail.com>, Alvaro
 Herrera <alvherre@2ndquadrant.com>, Ibrar Ahmed <ibrar.ahmad@gmail.com>,
 Amit Khandekar <amitdkhan.pg@gmail.com>, fabriziomello@gmail.com, tushar
 <tushar.ahuja@enterprisedb.com>, Rahila Syed <rahila.syed@2ndquadrant.com>,
  pgsql-hackers <pgsql-hackers@postgresql.org>
Date: Sun, 02 Apr 2023 15:15:44 -0700
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On Sun, 2023-04-02 at 14:35 -0700, Andres Freund wrote:
> Why not offer a function to add a CV to a WES? It seems somehow odd
> to require
> going through condition_variable.c to create a WES.

I agree that it's a bit odd, but remember that after waiting on a CV's
latch, it needs to re-insert itself into the CV's wait list.

A WaitEventSetWait() can't do that, unless we move the details of re-
adding to the wait list into latch.c. I considered that, but latch.c
already implements the APIs for WaitEventSet and Latch, so it felt
complex to also make it responsible for ConditionVariable.

I'm open to suggestion.

Regards,
	Jeff Davis