Re: MultiXactId error after upgrade to 9.3.4 - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: MultiXactId error after upgrade to 9.3.4
Date
Msg-id 20140423185120.GR25695@eldon.alvh.no-ip.org
Whole thread Raw
In response to Re: MultiXactId error after upgrade to 9.3.4  (Bruce Momjian <bruce@momjian.us>)
Responses Re: MultiXactId error after upgrade to 9.3.4
List pgsql-hackers
Bruce Momjian wrote:
> On Wed, Apr 23, 2014 at 03:42:14PM -0300, Alvaro Herrera wrote:
> > > > I still don't know under what circumstances this situation could arise.
> > > > This seems most strange to me.  I would wonder about this to be just
> > > > papering over a different bug elsewhere, except that we know this tuple
> > > > comes from a pg_upgraded table and so I think the only real solution is
> > > > to cope.
> > > 
> > > Shouldn't we log something at least if we are unsure of the cause?
> > 
> > I don't know.  Is it possible that XMAX_IS_MULTI got set because of
> > cosmic rays?  At this point that's the only explanation that makes sense
> > to me.  And I'm not sure what to do about this until we know more --
> > more user reports of this problem, for instance.
> > 
> > I don't see any reasonable way to distinguish this particular kind of
> > multixact-out-of-bounds situation from any other, so not sure what else
> > to log either (you can see that we already emit an error message.)
> 
> I guess I am lost then.  I thought it supressed the error.  What does
> the patch do?

You're right, it does.  I am not sure I would apply it.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services



pgsql-hackers by date:

Previous
From: Bruce Momjian
Date:
Subject: Re: MultiXactId error after upgrade to 9.3.4
Next
From: Andres Freund
Date:
Subject: Re: MultiXactId error after upgrade to 9.3.4