Re: primary/secondary/master/slave/standby

On Thu, May 27, 2010 at 9:22 AM, Heikki Linnakangas
<heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
> On 27/05/10 12:39, Dimitri Fontaine wrote:
>>
>> Greg Stark<gsstark(at)mit(dot)edu>  writes:
>>>
>>> Fwiw I like the word "replica" but I don't see an obvious choice of
>>> word to pair it with
>>
>> I guess it's replica / origin, per choice of Jan Wieck to be found in
>> our catalogs:
>>
>>  http://www.postgresql.org/docs/current/static/catalog-pg-trigger.html
>>
>>   tgenabled    char
>>
>>   Controls in which session_replication_role modes the trigger fires.
>>   O = trigger fires in "origin" and "local" modes, D = trigger is
>>   disabled, R = trigger fires in "replica" mode, A = trigger fires
>>   always.
>>
>> So that's origin/replica, master/slave, primary/standby, master/standby.
>
> master/standby is my favorite, and I believe we have a rough consensus on
> that.
>
> I started to search/replace primary -> master, but started to have second
> thoughts when I got to the section in the docs about standby servers:
>
> http://developer.postgresql.org/pgdocs/postgres/warm-standby.html
>
> Somehow that just doesn't sound as good after s/primary/master, the first
> sentence in particular. I think the reason is that "master" brings to mind
> an active connection between the master and standby, while "primary" sounds
> more loosely-coupled.
>
> Perhaps we should use master/standby when discussing streaming replication,
> and primary/standby when talking about a standby setup in general, possibly
> using file-based log shipping. The distinction is quite vague, so we'll have
> to document both terms as synonyms of each other.

I agree. I think it might make sense to try to standardize on the use
of "master" in messages (and GUC variable names) but insisting that we
can never say "primary" in the docs would make them read very oddly, I
think.

--
Robert Haas
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