Re: Optimization of vacuum for logical replication

On 21.08.2019 14:45, Bernd Helmle wrote:
> Am Mittwoch, den 21.08.2019, 13:26 +0300 schrieb Konstantin Knizhnik:
>> Yes, it is possible to have physical replica withotu replication
>> slot.
>> But it is not safe, because there is always a risk that lag between
>> master and replica becomes larger than size of WAL kept at master.
> Sure, but that doesn't mean use cases for this aren't real.
>
>> Also I can't believe that DBA which explicitly sets wal_level is set
>> to
>> logical will use streaming replication without associated replication
>> slot.
> Well, i know people doing exactly this, for various reasons (short
> living replicas, logical replicated table sets for reports, ...). The
> fact that they can have loosely coupled replicas with either physical
> or logical replication is a feature they'd really miss....
>
> Bernd
>

Ok, you convinced me that there are cases when people want to combine
logical replication with streaming replication without slot.
But is it acceptable to have GUC variable (disabled by default) which
allows to use this optimizations?

--
Konstantin Knizhnik
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