Re: old_snapshot_threshold documentation

On Fri, Aug 26, 2016 at 1:34 PM, Peter Eisentraut
<peter(dot)eisentraut(at)2ndquadrant(dot)com> wrote:
> I doubt the documentation for old_snapshot_threshold is going to be
> understood by many ordinary users. What is a "snapshot", first of all?
> Why would a snapshot be old? Why is that a problem? What can I do to
> avoid it? What are the circumstances in practice where this issue would
> arise, and what are the trade-offs? Where can I see existing snapshots
> and how old they are?

I'll put something together to improve that. I think largely that
will consist of references to other sections of the documentation,
like MVCC, vacuuming, pg_stat_activity, etc.

--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company