From: Joshua D. Drake <jd@commandprompt.com>
To: Andres Freund <andres@anarazel.de>
To: pgsql-hackers@lists.postgresql.org, pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: replication_slots usability issue
Date: Mon, 29 Oct 2018 15:13:07 -0700
Message-ID: <cc681364-c4e3-c288-fd6f-b7a8b52c3fa4@commandprompt.com> (raw)
In-Reply-To: <835C001D-7F0B-4C90-BFB3-5D6EE5E71A21@anarazel.de>
References: <56672097-711c-126a-a63e-04e7940110ad@commandprompt.com>
<835C001D-7F0B-4C90-BFB3-5D6EE5E71A21@anarazel.de>
On 10/29/18 11:26 AM, Andres Freund wrote:
>
> On October 29, 2018 1:31:56 PM EDT, "Joshua D. Drake" <jd@commandprompt.com> wrote:
>> -Hackers,
>>
>>
>> Working on 9.6 today (unsure if fixed in newer versions). Had an issue
>> where the wal was 280G despite max_wal_size being 8G. Found out there
>> were stale replication slots from a recent base backup. I went to drop
>> the replication slots and found that since the wal_level was set to
>> minimal vs replica or higher, I couldn't drop the replication slot.
>> Clearly that makes sense for creating a replication slot but it seems
>> like an artificial limitation for dropping them.
> Uh, huh? How did you manage to start a server with existing slots with that configuration? It should have errored out at start...
Well, this is the recovery.conf:
standby_mode = 'on'
recovery_target = 'immediate'
primary_slot_name = 'testing_db01'
primary_conninfo = 'user=replication
passfile=/var/lib/postgresql/.pgpass host=db01 port=5432 sslmode=prefer
sslcompression=1 krbsrvname=postgres target_session_attrs=any'
recovery_target_action = 'promote'
The machine came up clean and the only reason I noticed the problem is
that it ran out of disk space. I cleared enough disk space to get it to
come up again and noticed that there were replication slots that were
identical to the primary.
JD
--
Command Prompt, Inc. || http://the.postgres.company/ || @cmdpromptinc
*** A fault and talent of mine is to tell it exactly how it is. ***
PostgreSQL centered full stack support, consulting and development.
Advocate: @amplifypostgres || Learn: https://postgresconf.org
***** Unless otherwise stated, opinions are my own. *****
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: jd@commandprompt.com, andres@anarazel.de
Subject: Re: replication_slots usability issue
In-Reply-To: <cc681364-c4e3-c288-fd6f-b7a8b52c3fa4@commandprompt.com>
* 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