Re: heap metapages

On 24 May 2012 23:02, Bruce Momjian <bruce@momjian.us> wrote:
> On Tue, May 22, 2012 at 09:52:30AM +0100, Simon Riggs wrote:
>> Having pg_upgrade touch data files is both dangerous and difficult to
>> back out in case of mistake, so I am wary of putting the metapage at
>> block 0. Doing it the way I suggest means the .meta files would be
>> wholly new and can be deleted as a back-out. We can also clean away
>> any unnecessary .vm/.fsm files as a later step.
>
> Pg_upgrade never modifies the old cluster, except to lock it in link
> mode, so there is never anything to back out.

Agreed. Robert's proposal was to make pg_upgrade modify the cluster,
which I was observing wasn't a good plan.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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