Re: loss of transactions in streaming replication

Fujii Masao <masao.fujii@gmail.com>

From: Fujii Masao <masao.fujii@gmail.com>

To: Robert Haas <robertmhaas@gmail.com>

Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>

Date: 2011-10-21T01:51:01Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Send status updates back from standby server to master, indicating how far
- b186523fd97c 9.1.0 cited
Allow bidirectional copy messages in streaming replication mode.
- d3d414696f39 9.1.0 cited

On Thu, Oct 20, 2011 at 1:05 AM, Robert Haas <robertmhaas@gmail.com> wrote:
> OK, so this is an artifact of the changes to make libpq communication
> bidirectional.  But I'm still confused about where the error is coming
> from.  In your OP, you wrote "In 9.2dev and 9.1, when walreceiver
> detects an error while sending data to WAL stream, it always emits
> ERROR even if there are data available in the receive buffer."  So
> that implied to me that this is only going to trigger if you have a
> shutdown together with an awkwardly-timed error.  But your scenario
> for reproducing this problem doesn't seem to involve an error.

Yes, my scenario doesn't cause any real error. My original description was
misleading. The following would be closer to the truth:

    "In 9.2dev and 9.1, when walreceiver detects the termination of replication
    connection while sending data to WAL stream, it always emits ERROR
    even if there are data available in the receive buffer."

Regards,

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