Re: page corruption on 8.3+ that makes it to standby

On Thu, Jul 29, 2010 at 4:58 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> On Wed, 2010-07-28 at 14:22 -0700, Jeff Davis wrote:
>> On Wed, 2010-07-28 at 15:37 -0400, Tom Lane wrote:
>> > So nevermind that distraction.  I'm back to thinking that fix1 is
>> > the way to go.
>>
>> Agreed.
>>
>> It's uncontroversial to have a simple guard against corrupting an
>> uninitialized page, and uncontroversial is good for things that will be
>> back-patched.
>
> Still don't understand why we would not initialize such pages. If we're
> copying a relation we must know enough about it to init a page.

Well, I don't see why we'd want to do that. As Jeff Davis pointed
out, if someone asks to move a table to a different tablespace,
changing the contents as we go along seems a bit off-topic. But the
bigger problem is you haven't explained how you think we could
determine what initialization ought to be performed. There's no
index-AM API that says "initialize this page". I suppose we could
invent one if there were some benefit, but we couldn't very well
back-patch such a thing to 8.0.

--
Robert Haas
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