Re: Standbys, txid_current_snapshot, wraparound

On Fri, Mar 23, 2012 at 12:26 AM, Daniel Farina <daniel(at)heroku(dot)com> wrote:

> Some time ago I reported bug 6291[0], which reported a Xid wraparound,
> both as reported in pg_controldata and by txid_current_snapshot.
> Unfortunately, nobody could reproduce it.
>
> Today, the same system of ours just passed the wraparound mark
> successfully at this time, incrementing the epoch.  However, two
> standbys have not done the same: they have wrapped to a low txid.  At
> this time, pg_controldata does report the correct epoch, as I read it,
> unlike the original case.
>
> I have not yet tried to reproduce this in a minimal way, but I wanted
> to relate this information as soon as possible.
>
> These systems are 9.0.6, on Ubuntu 10.04 LTS, amd64.
>
> [0]: http://archives.postgresql.org/pgsql-bugs/2011-11/msg00094.php

So we have this?

Master pg_controldata - OK txid_current_snapshot() - OK
Standby pg_controldata - OK txid_current_snapshot() - lower value

Are there just 2 standbys? So all standbys have acted identically?

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