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

On 2014-03-31 08:54:53 -0300, Alvaro Herrera wrote:
> My conclusion here is that some part of the code is failing to examine
> XMAX_INVALID before looking at the value stored in xmax itself.  There
> ought to be a short-circuit.  Fortunately, this bug should be pretty
> harmless.
> 
> .. and after looking, I'm fairly sure the bug is in
> heap_tuple_needs_freeze.

heap_tuple_needs_freeze() isn't *allowed* to look at
XMAX_INVALID. Otherwise it could miss freezing something still visible
on a standby or after an eventual crash.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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