Hi,
On 2019-06-07 21:16:12 -0400, Chapman Flack wrote:
> On 06/07/19 21:01, Andres Freund wrote:
> > On 2019-06-07 20:52:38 -0400, Chapman Flack wrote:
> > That'd be a *lot* of additional complexity, and pretty much prohibitive
> > from a performance POV. We'd have to not continue decoding on the server
> > side *all* the time to give the client a chance to inquire additional
> > information.
>
> Does anything travel in the client->server direction during replication?
> I thought I saw CopyBoth mentioned. Is there a select()/poll() being done
> so those messages can be received?
Yes, acknowledgements of how far data has been received (and how far
processed), which is then used to release resources (WAL, xid horizon)
and allow synchronous replication to block until something has been
received.
- Andres