Re: Logical Replication WIP

On 21/09/16 05:35, Steve Singer wrote:
> On Tue, 20 Sep 2016, Peter Eisentraut wrote:
>
>> On 9/18/16 4:17 PM, Steve Singer wrote:
>
>>
>> I think if we want to prevent the creation of subscriptions that point
>> to self, then we need to create a magic token when the postmaster starts
>> and check for that when we connect. So more of a running-instance
>> identifier instead of a instance-on-disk identifier.
>>
>> The other option is that we just allow it and make it more robust.
>
> I think we should go with the second option for now. I feel that the
> effort is better spent making sure that initial syncs that have don't
> subscribe (for whatever reasons) can be aborted instead of trying to
> build a concept of node identity before we really need it.
>

Well connecting to yourself will always hang though because the slot
creation needs snapshot and it will wait forever for the current query
to finish. So it will never really work. The hanging query is now
abortable though.

Question is if doing the logical snapshot is really required since we
don't really use the snapshot for anything here.

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