Re: Logical Replication WIP

Petr Jelinek wrote:
> On 09/08/16 10:13, Craig Ringer wrote:

> >The only argument I can see for not using bgworkers is for the
> >supervisor worker. It's a singleton that launches the per-database
> >workers, and arguably is a job that the postmaster could do better. The
> >current design there stems from its origins as an extension. Maybe
> >worker management could be simplified a bit as a result. I'd really
> >rather not invent yet another new and mostly duplicate category of
> >custom workers to achieve that though.
> 
> It is simplified compared to pglogical (there is only 2 worker types not 3).
> I don't think it's job of postmaster to scan catalogs however so it can't
> really start workers for logical replication. I actually modeled it more
> after autovacuum (using bgworkers though) than the original extension.

Yeah, it's a very bad idea to put postmaster on this task.  We should
definitely stay away from that.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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