Re: Freeze avoidance of very large table.

On Mon, Dec 21, 2015 at 3:27 AM, Kyotaro HORIGUCHI
<horiguchi.kyotaro@lab.ntt.co.jp> wrote:
> Hello,
>
> At Fri, 18 Dec 2015 12:09:43 -0500, Robert Haas <robertmhaas@gmail.com> wrote in
<CA+TgmoZCCFwgKL0PmSi=htfZ2aCOZPoTPD73ecvSA9rhXa0zUw@mail.gmail.com>
>> On Thu, Dec 17, 2015 at 1:17 AM, Michael Paquier
>> <michael.paquier@gmail.com> wrote:
>> > I am not really getting the meaning of this sentence. Shouldn't this
>> > be reworded something like:
>> > "Freezing occurs on the whole table once all pages of this relation require it."
>>
>> That statement isn't remotely true, and I don't think this patch
>> changes that.  Freezing occurs on the whole table once relfrozenxid is
>> old enough that we think there might be at least one page in the table
>> that requires it.
>
> I doubt I can explain this accurately, but I took the original
> phrase as that if and only if all pages of the table are marked
> as "requires freezing" by accident, all pages are frozen. It's
> quite obvious but it is what I think "happen to require freezing"
> means. Does this make sense?
>
> The phrase might not be necessary if this is correct.

Maybe you are trying to say something like "only those pages which
require freezing are frozen?".

-- 
Robert Haas
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