Re: Wraparound warning

On Tue, Oct 25, 2016 at 01:19:26PM -0400, Robert Haas wrote:
> On Tue, Oct 25, 2016 at 11:20 AM, Bruce Momjian <bruce@momjian.us> wrote:
> > Do we still need to report the wraparound warning on server startup?
> >
> >         LOG:  MultiXact member wraparound protections are now enabled
> >
> > I thought that was going to be removed at some point, no?
> 
> If you start with a 9.3.small cluster and do a pg_upgrade to 10, you
> could end up not seeing that message and not having those protections
> enabled, and it would be useful to be able to tell that from looking
> at the log.

Uh, I am confused.  I am seeing this on a fresh PG 10 initdb'ed cluster,
not one pg_upgraded.  Is that expected?

> Maybe what we should do (since this message obviously annoys everyone)

It is a persistent reminder our of engineering failure.  I guess it
should annoy us, and maybe that's OK.

> is change things so that, starting in v10, a message is logged at
> startup if those protections are NOT enabled, and nothing is logged if
> they are enabled.  Keep the message for the case where protections are
> enabled later, after startup time.

How are those protections enabled/disabled?

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com

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