Re: Planning incompatibilities for Postgres 10.0

Bruce Momjian wrote:
> On Mon, May 27, 2013 at 03:06:13PM -0400, Alvaro Herrera wrote:
> > Bruce Momjian wrote:

> > I would have each data segment be self-identifying, i.e. have a magic
> > number at the beginning of the file and the relation OID, some fork
> > identification and the segment number somewhere -- probably the special
> > space of the first page.
> 
> Is this something we want on the TODO?  I was not clear how to do with
> without making the first page format special or wasting space on all the
> other pages.

I don't think the special space has to necessarily be identically sized
in all the pages -- I admit I haven't looked closely, but the special
size is part of the page header.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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