Re: Horizontal scalability/sharding

On 2015-09-03 12:10:08 -0400, Robert Haas wrote:
> On Thu, Sep 3, 2015 at 6:57 AM, Bruce Momjian <bruce@momjian.us> wrote:
> > Yes, I assumed that.  Logical replication uses WAL, so if you are
> > synchronous with WAL, logical replication is synchronous too.  However,
> > of course, it is synchronous in being durable, not synchronous in terms
> > of applying the WAL.  This is true of binary and logical replication.

Actually that's not really true - it's just a question which LSNs you
return. For UDR/BDR the relevant LSN is the LSN of the last durably
committed transaction. And thus they wait for apply, not anything else.

> But, Thomas Munro is fixing it!

+ many to that effort.

Greetings,

Andres Freund