Message-ID: <1521449580.3335.18.camel@cybertec.at>
Subject: Re: Will unused replication slots prevent the server from deleting
 WAL segments?
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Nagy =?ISO-8859-1?Q?L=E1szl=F3?= Zsolt <gandalf@shopzeus.com>,
	pgsql-admin@postgresql.org
Date: Mon, 19 Mar 2018 09:53:00 +0100
In-Reply-To: <73cd3a8f-363f-c880-67c7-9bcf290ba2b7@shopzeus.com>
References: <73cd3a8f-363f-c880-67c7-9bcf290ba2b7@shopzeus.com>
Organization: Cybertec
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Nagy László Zsolt wrote:
> I have accidentally created an extra replication slot on a server. It
> was a long time ago, and it is not used (active=false). I'm planning to
> add another replication slave, but I can only do it later. I wonder if
> it prevents the server to recycle old WAL segments?
> 
> 
> template1=# select * from pg_replication_slots;
>  slot_name | plugin | slot_type | datoid | database | temporary | active
> > active_pid | xmin | catalog_xmin | restart_lsn | confirmed_flush_lsn
> 
> -----------+--------+-----------+--------+----------+-----------+--------+------------+------+--------------+-------------+---------------------
>  eke       |        | physical  |        |          | f         | f     
> >             |      |              |             |
> 
>  docker02  |        | physical  |        |          | f         | t     
> >          66 |      |              | 0/7000000   |
> 
> (2 rows)
>  
> 
> Should I delete this slot and add it again later, when the new slave
> becomes available?

I'm not 100% certain if it can do any harm or not, but I'd drop the
replication slot and create a new one later if you need it.

Creating a replication slot is fast and simple.

Yours,
Laurenz Albe
-- 
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