Re: Replication/backup defaults

On 3 January 2017 at 12:34, Michael Paquier <michael(dot)paquier(at)gmail(dot)com> wrote:
> On Mon, Jan 2, 2017 at 10:55 PM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
>> In the hope of making things better in 10.0, I remove my objection. If
>> people want to use wal_level = minimal they can restart their server
>> and they can find that out in the release notes.
>>
>> Should we set wal_level = replica or wal_level = logical as the
>> default for 10.0?
>
> replica sounds like a better default to me as most users use at least
> archiving. Logical decoding is still fresh though, and its use is not
> that wide. Have there been any study on its performance impact
> compared to replica by the way?

Magnus' arguments should also be applied to wal_level = logical since
users will be surprised if they cannot use the logical replication
features we are adding as a main feature of 10.0. Why go through the
same pain again?

And if preventing their use is acceptable for the user, we should
treat it as a performance feature to reduce the wal_level.

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