Subject: Re: Change default of checkpoint_completion_target
To: Stephen Frost <sfrost@snowman.net>, Michael Paquier <michael@paquier.xyz>
References: <20201207175329.GM16415@tamriel.snowman.net>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>,
 "Bossart, Nathan" <bossartn@amazon.com>,
 Laurenz Albe <laurenz.albe@cybertec.at>, Bernd Helmle
 <mailings@oopsware.de>,
 "tsunakawa.takay@fujitsu.com" <tsunakawa.takay@fujitsu.com>,
 "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
From: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Organization: EnterpriseDB
Message-ID: <5285eb02-3340-7728-9f62-1a4365eda850@enterprisedb.com>
Date: Mon, 7 Dec 2020 20:08:25 +0100
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On 2020-12-07 18:53, Stephen Frost wrote:
> * Michael Paquier (michael@paquier.xyz) wrote:
>> On Sun, Dec 06, 2020 at 10:03:08AM -0500, Stephen Frost wrote:
>>> * Alvaro Herrera (alvherre@alvh.no-ip.org) wrote:
>>>> You keep making this statement, and I don't necessarily disagree, but if
>>>> that is the case, please explain why don't we have
>>>> checkpoint_completion_target set to 0.9 by default?  Should we change
>>>> that?
>>>
>>> Yes, I do think we should change that..
>>
>> Agreed.  FWIW, no idea for others, but it is one of those parameters I
>> keep telling to update after a default installation.
> 
> Concretely, attached is a patch which changes the default and updates
> the documentation accordingly.

I agree with considering this change, but I wonder why the value 0.9. 
Why not, say, 0.95, 0.99, or 1.0?