Re: [Proposal] More Vacuum Statistics

Hi,

On 05/30/15 04:41, Andres Freund wrote:
> On 2015-05-29 21:30:57 -0500, Jim Nasby wrote:
>> It occurs to me that there's no good reason for vacuum-derived stats to be
>> in the stats file; it's not like users run vacuum anywhere near as often as
>> other commands. It's stats could be kept in pg_class; we're already keeping
>> things like relallvisible there.
>
> While it might be viable to store them somewhere but the stat files,
> I don't think pg_class is a good place. Its size is not any less
> critical than the stats files. I.e. reading it sits in several rather
> hot paths, and we keep tuples from it in memory in a lot of places.

IMHO stat files is exactly the right place for data like this - I can't
really think about other place with less overhead / impact. That of
course assumes the new fields really are useful, and I do have my doubts
about usefulness of this data.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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