Thread: Streaming Replication and CopyOutResponse message

Hi,

At the end of the handshake for replication, a CopyOutResponse
message might not arrive at the standby for a while if there is
no WAL record to send. Also walreceiver would get stuck until
that message has arrived. This is not a big problem, but should
be fixed.

The cause is that walsender hasn't called pq_flush() there.
The attached patch changes walsender so as to call pg_flush()
immediately when sending that message. Is it worth applying
the patch?

Regards,

--
Fujii Masao
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center

Fujii Masao wrote:
> At the end of the handshake for replication, a CopyOutResponse
> message might not arrive at the standby for a while if there is
> no WAL record to send. Also walreceiver would get stuck until
> that message has arrived. This is not a big problem, but should
> be fixed.
> 
> The cause is that walsender hasn't called pq_flush() there.
> The attached patch changes walsender so as to call pg_flush()
> immediately when sending that message. Is it worth applying
> the patch?

Yeah, applied.

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