Horton

Re: XMin Hot Standby Feedback patch

Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>

View thread
From: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Simon Riggs <simon@2ndquadrant.com>, Daniel Farina <daniel@heroku.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2011-02-15T16:54:22Z
Lists: pgsql-hackers 
On 15.02.2011 18:52, Robert Haas wrote:
> On Tue, Feb 15, 2011 at 11:49 AM, Heikki Linnakangas
> <heikki.linnakangas@enterprisedb.com>  wrote:
>> It would be wise to also transmit the epoch in addition to xmin, to avoid
>> confusion if the standby is>  2 billion transactions behind.
>
> That case is probably hopelessly broken anyway.

I don't expect the feedback to do anything too useful in case of xid 
wraparound, but at least the master would recognize the situation and 
know to ignore the bogus xmin from that standby.

-- 
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com