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.
Greg Smith had this idea about "timing events",
https://www.postgresql.org/message-id/50A4BC4E.4030007%402ndQuadrant.com
Sounds like this thread is related.
--
Álvaro Herrera http://www.2ndQuadrant.com/
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