Re: recovery_target_time and standby_mode - Mailing list pgsql-hackers

From Josh Berkus
Subject Re: recovery_target_time and standby_mode
Date
Msg-id 54639501.8040700@agliodbs.com
Whole thread Raw
In response to recovery_target_time and standby_mode  (Josh Berkus <josh@agliodbs.com>)
Responses Re: recovery_target_time and standby_mode  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
On 11/07/2014 02:03 PM, Josh Berkus wrote:
> But, like I said, there's a serviceable workaround.

Some update on this.  We've seen a problem in production with this setup
which I can't reproduce as a test case, but which may jog Heikki's
memory for something to fix.

1. Recover master to 2014-11-10 12:10:00
2. Recover replica to 2014-11-10 12:10:00,  with pause_at_recovery_target
3. reconfigure recovery.conf for streaming replication  and restart the replica
4. get a fatal error for replication, because  the replica is ahead of the master on timeline1

What *appears* to be happening is that the pause_at_recovery_target,
followed by the restart, on the replica causes it to advance one commit
on timeline 1.  But *not all the time*; this doesn't happen in my
pgbench-based tests.

There's a workaround for the user (they just restore the replica to 5
minutes earlier), but I'm thinking this is a minor bug somewhere.

-- 
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com



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