Re: pg_stat_statements: calls under-estimation propagation

Daniel Farina <drfarina@acm.org>

From: Daniel Farina <drfarina@acm.org>
To: Peter Geoghegan <peter@2ndquadrant.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2012-12-29T13:02:46Z
Lists: pgsql-hackers

Attachments

On Sat, Dec 29, 2012 at 4:21 AM, Daniel Farina <drfarina@acm.org> wrote:
> These were not express goals of the patch, but so long as you are
> inviting features, attached is a bonus patch that exposes the queryid
> and also the notion of a "statistics session" that is re-rolled
> whenever the stats file could not be read or the stats are reset, able
> to fully explain all obvious causes of retrograde motion in
> statistics.  It too is cumulative, so it includes the under-estimation
> field.  Notably, I also opted to nullify extra pg_stat_statements
> fields when they'd also show "insufficient privileges" (that one is
> spared from this censorship), because I feel as though a bit too much
> information leaks from pg_stat_statement's statistics to ignore,
> especially after adding the query id.  Since the common theme here is
> identifying queries, I have called it
> "pg_stat_statements-identification", and it can be found in the git
> repo above under the same name (...-v1).

A small amendment that doesn't really change the spirit of the
narrative is attached.

--
fdr

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Improve management of "sticky" entries in contrib/pg_stat_statements.