Re: Freeze avoidance of very large table.

On Wed, Apr 22, 2015 at 12:02 AM, Andres Freund <andres@anarazel.de> wrote:
> On 2015-04-21 23:59:45 +0900, Sawada Masahiko wrote:
>> The page as frozen could have the dead tuple for now, but I think to change
>> to that the frozen page guarantees that page is all frozen *and* all
>> visible.
>
> It shouldn't. That'd potentially cause corruption after a wraparound. A
> tuple's visibility might change due to that.

The page as frozen could have some dead tuples, right?
I think we should to clear a bit of FrozenMap (and flag of page
header) on delete operation, and a bit is set only by vacuum.
So accordingly, the page as frozen guarantees that all frozen and all visible?

Regards,

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Sawada Masahiko