Re: Hot Standby (v9d)

On Wed, 2009-01-28 at 21:41 +0200, Heikki Linnakangas wrote:

> So, you can think of the unobserved xids array as an extension of 
> ProcArray. The entries are like light-weight PGPROC entries. In fact I
> proposed earlier to simply create dummy PGPROC entries instead.

Which we don't do because we don't know whether we are dealing with
top-level xids or subtransactions of already observed top-level xids.

Either way we have to rearrange things when we move from unobserved to
observed. A major difference is that what we have now works and what we
might have instead may not, which is being illustrated by recent
testing.

-- Simon Riggs           www.2ndQuadrant.comPostgreSQL Training, Services and Support