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Date: Tue, 2 May 2017 12:49:59 -0300
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Petr Jelinek <petr.jelinek@2ndquadrant.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Robert Haas <robertmhaas@gmail.com>,
	Michael Paquier <michael.paquier@gmail.com>,
	PostgreSQL mailing lists <pgsql-hackers@postgresql.org>
Subject: Re: logical replication syntax (was DROP SUBSCRIPTION,
 query cancellations and slot handling)
Message-ID: <20170502154959.r45gitdimklbcrwt@alvherre.pgsql>
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Petr Jelinek wrote:

> So the only way to fulfill the requirement you stated is to just not try
> to drop the slot, ever, on DROP SUBSCRIPTION. That makes the default
> behavior leave resources on upstream that will eventually cause that
> server to stop unless user notices before. I think we better invent
> something that limits how much inactive slots can hold back WAL and
> catalog_xmin in this release as well then.

I don't understand why isn't the default behavior to unconditionally
drop the slot.  Why do we ever want the slot to be kept?

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


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