Re: Logical replication launcher's bgworker enabled by default, and max_logical_replication_workers

On 23/01/17 05:37, Michael Paquier wrote:
> Hi all,
>
> When spawning a new instance, I found the following thing, which is
> surprising at first sight:
> postgres: bgworker: logical replication launcher
>
> There is perhaps no problem to keep that enabled by default until the
> release 10 wraps to give it some buildfarm coverage similarly to what
> has been done last year for parallel query, but what is surprising me
> is that even if wal_level is *not* logical this gets started. I think
> that something like the patch attached is needed, so as
> ApplyLauncherRegister() is a noop if wal_level < logical.
>

As discussed elsewhere, there is no need for wal_level = logical
downstream and launcher is only needed for downstream.

--
Petr Jelinek http://www.2ndQuadrant.com/
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