From: PG Bug reporting form <noreply@postgresql.org>
To: pgsql-bugs@lists.postgresql.org
Cc: jobin.augustine@percona.com
Subject: BUG #17196: old_snapshot_threshold is not honored if there is a transaction
Date: Mon, 20 Sep 2021 06:14:56 +0000
Message-ID: <17196-6c6c9e476971c07c@postgresql.org> (raw)
The following bug has been logged on the website:
Bug reference: 17196
Logged by: Jobin Augustine
Email address: jobin.augustine@percona.com
PostgreSQL version: 13.4
Operating system: Any
Description:
I am not quite sure whether this should be called a "Bug". But I thought of
reporting because many suffer and has a potential for user abuse.
Problem:
A user can just create a table and then issue SELECT ... FOR UPDATE on that
table. This will prevent all vacuums to be held up across all tables in
PostgreSQL, even if we set a limit to old_snapshot_threshold. The entire
database will become heavily bloated, hence unresponsive, resulting in a
service denial situation.
This is causing problems for OpenSource Projects like ActiveMQ when they use
PostgreSQL (They are using workarounds now).
http://spatula.net/mt/blog/2014/02/postgresql-activemq-autovacuum-hell.html
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To: pgsql-bugs@postgresql.org
Cc: noreply@postgresql.org, pgsql-bugs@lists.postgresql.org, jobin.augustine@percona.com
Subject: Re: BUG #17196: old_snapshot_threshold is not honored if there is a transaction
In-Reply-To: <17196-6c6c9e476971c07c@postgresql.org>
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