Horton

Re: loss of transactions in streaming replication

Fujii Masao <masao.fujii@gmail.com>

View thread
From: Fujii Masao <masao.fujii@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2011-10-13T01:08:37Z
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 →

  1. Send status updates back from standby server to master, indicating how far

  2. Allow bidirectional copy messages in streaming replication mode.

On Wed, Oct 12, 2011 at 10:29 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> On Wed, Oct 12, 2011 at 5:45 AM, Fujii Masao <masao.fujii@gmail.com> 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. This might lead to loss of transactions because such
>> remaining data are not received by walreceiver :(
>
> Won't it just reconnect?

Yes if the master is running normally. OTOH, if the master is not running (i.e.,
failover case), the standby cannot receive again the data which it failed to
receive.

I found this issue when I shut down the master. When the master shuts down,
it sends the shutdown checkpoint record, but I found that the standby failed
to receive it.

Regards,

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