Re: ACK from walreceiver to walsender

Fujii Masao wrote:
> Hi Heikki,
>
> http://git.postgresql.org/gitweb?p=users/heikki/postgres.git;a=commit;h=ebaa89ce8906e0ec45f105d083a0360b1f8bc7ca
>
> You dropped all the ACKs from walreceiver to walsender. I have no objection
> to that, but I think that walsender should handle at least 'X' (which means
> that the standby is closing down the socket) and EOF (which means unexpected
> loss of standby connection) messages from walreceiver. Otherwise, walsender
> might be unable to detect the shutdown of walreceiver for a while.

Yeah, I just noticed that myself :-(. I guess we'll still have to use
select() in the walreceiver loop to detect that then.

I don't think we need to treat 'X' differently from EOF. You get an
error anyway if the write() fails. That's actually a bit annoying, you
get a "could not send data to client" error in the log every time a
standby disconnects for any reason.

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com