Re: Bi-Directional replication client awareness

12 jul 2014 kl. 12:33 skrev Andres Freund <andres(at)2ndquadrant(dot)com>:

> On 2014-07-12 18:22:30 +0800, Craig Ringer wrote:
>> On 07/12/2014 02:24 PM, Martin Gudmundsson wrote:
>>> Any ideas giving BDR an option to be synchronous. I mean in ”close quarters” with low latency it should work ok.
>>
>> BDR doesn't do synchronous replication _yet_, but it's on the roadmap.
>
> Just to clarify: There's two things that sometimes are referred to as
> 'synchronous' in the context of multimaster replication.
>
> Just like with HS' builtin synchronous replication it can mean that the
> client doesn't get a reply until the COMMIT has safely been replicated
> to other systems. That's supported by BDR today.

Would that be to a streaming replication synchronous standby? I.e replicated to a read only node?

> The more complex thing is support for performing transactions that, when
> the COMMIT returns successfully, can't have conflicts. That's *not* yet
> supported, but we're thinking of implementing it for individual
> transactions.
>
> Greetings,
>
> Andres Freund
>
> --
> Andres Freund http://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Training & Services