Ensure no xid gaps during Hot Standby startup

Simon Riggs <simon@2ndQuadrant.com>

Commit: f44eedc3f0f347a856eea8590730769125964597
Author: Simon Riggs <simon@2ndQuadrant.com>
Date: 2013-06-23T13:50:38Z
Releases: 9.0.14
Ensure no xid gaps during Hot Standby startup

In some cases with higher numbers of subtransactions
it was possible for us to incorrectly initialize
subtrans leading to complaints of missing pages.

Bug report by Sergey Konoplev
Analysis and fix by Andres Freund

Files