Re: Freeze avoidance of very large table.

On Mon, Oct 5, 2015 at 11:03 PM, Fujii Masao <masao.fujii@gmail.com> wrote:
> On Fri, Oct 2, 2015 at 8:14 PM, Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>>> +#define Anum_pg_class_relallfrozen        12
>>> Why is pg_class.relallfrozen necessary? ISTM that there is no user of it now.
>>
>> The relallfrozen would be useful for user to estimate time to vacuum
>> freeze or anti-wrapping vacuum before being done them actually.
>> (Also this value is used on regression test.)
>> But this information is not used on planning like relallvisible, so it
>> would be good to move this information to another system view like
>> pg_stat_*_tables.
>
> Or make pgstattuple and pgstattuple_approx report even the number
> of frozen tuples?
>

But we cannot know the number of frozen pages without installation of
pageinspect module.
I'm a bit concerned about that the all projects cannot install
extentension module into postgresql on production environment.
I think we need to provide such feature at least into core.
Thought?

Regards,

--
Masahiko Sawada