Re: Logical Replication WIP

On 1/15/17 5:20 PM, Petr Jelinek wrote:
> Well, it's 4 because max_worker_processes is 8, I think default
> max_worker_processes should be higher than
> max_logical_replication_workers so that's why I picked 4. If we are okay
> wit bumping the max_worker_processes a bit, I am all for increasing
> max_logical_replication_workers as well.
>
> The quick setup mentions 10 mainly for consistency with slots and wal
> senders (those IMHO should also not be 0 by default at this point...).

Those defaults have now been changed, so the "Quick setup" section could
potentially be simplified a bit.

> I did this somewhat differently, with struct that defines options and
> has different union members for physical and logical replication. What
> do you think of that?

Looks good.

>> Not sure about
>> worker_internal.h. Maybe rename apply.c to worker.c?
>>
>
> Hmm I did that, seems reasonably okay. Original patch in fact had both
> worker.c and apply.c and I eventually moved the worker.c functions to
> either apply.c or launcher.c.

I'm not too worried about this.

> Yes, that will need some discussion about corner case behaviour. For
> example, have partitioned table 'foo' which is in publication, then you
> have table 'bar' which is not in publication, you attach it to the
> partitioned table 'foo', should it automatically be added to
> publication? Then you detach it, should it then be removed from publication?
> What if 'bar' was in publication before it was attached/detached to/from
> 'foo'? What if 'foo' wasn't in publication but 'bar' was? Should we
> allow ONLY syntax for partitioned table when they are being added and
> removed?

Let's think about that in a separate thread.

>> reread_subscription() complains if the subscription name was changed.
>> I don't know why that is a problem.
>
> Because we don't have ALTER SUBSCRIPTION RENAME currently. Maybe should
> be Assert?

Is there anything stopping anyone from implementing it?

I'm happy with these patches now.

--
Peter Eisentraut http://www.2ndQuadrant.com/
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