Re: remove wal_level archive

On 1 September 2015 at 03:39, Peter Eisentraut <peter_e(at)gmx(dot)net> wrote:

> - The distinction between wal_level settings "archive" and "hot_standby"
> is in the way of automation or better intelligence, because the primary
> cannot tell what the receiver intends to do with the WAL.
>
> So here is a patch to get rid of the distinction.
>
> Bike-shedding: In this patch, I removed "archive" and kept
> "hot_standby", because that's what the previous discussions suggested.
> Historically and semantically, it would be more correct the other way
> around. On the other hand, keeping "hot_standby" would probably require
> fewer configuration files to be changed. Or we could keep both, but
> that would be confusing (for users and in the code).
>

I've reviewed this and have a few comments.

Removing one of "archive" or "hot standby" will just cause confusion and
breakage, so neither is a good choice for removal.

What we should do is
1. Map "archive" and "hot_standby" to one level with a new name that
indicates that it can be used for both/either backup or replication.
(My suggested name for the new level is "replica"...)
2. Deprecate "archive" and "hot_standby" so that those will be removed in a
later release.

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Simon Riggs http://www.2ndQuadrant.com/
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