From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Robert Haas <robertmhaas@gmail.com>
Cc: pgsql-hackers@postgresql.org <pgsql-hackers@postgresql.org>
Subject: Re: when the startup process doesn't
Date: Mon, 19 Apr 2021 19:16:37 -0400
Message-ID: <20210419231637.GA24815@alvherre.pgsql> (raw)
In-Reply-To: <CA+TgmoaHQrgDFOBwgY16XCoMtXxsrVGFB2jNCvb7-ubuEe1MGg@mail.gmail.com>
On 2021-Apr-19, Robert Haas wrote:
> Another possible approach would be to accept connections for
> monitoring purposes even during crash recovery. We can't allow access
> to any database at that point, since the system might not be
> consistent, but we could allow something like a replication connection
> (the non-database-associated variant).
Hmm. We already have pg_isready, which is pretty simplistic -- it tries
to connect to the server and derive a status in a very simplistic way.
Can we perhaps improve on that? I think your idea of using the
non-database-connected replication mode would let the server return a
tuple with some status information with a new command. And then
pg_isready could interpret that, or just print it.
--
Álvaro Herrera 39°49'30"S 73°17'W
Subversion to GIT: the shortest path to happiness I've ever heard of
(Alexey Klyukin)
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-hackers@postgresql.org
Cc: alvherre@alvh.no-ip.org, robertmhaas@gmail.com
Subject: Re: when the startup process doesn't
In-Reply-To: <20210419231637.GA24815@alvherre.pgsql>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox