Re: Big problem with sql update operation - Mailing list pgsql-performance

From Alvaro Herrera
Subject Re: Big problem with sql update operation
Date
Msg-id 20070525223828.GE24789@alvh.no-ip.org
Whole thread Raw
In response to Re: Big problem with sql update operation  (Michal Szymanski <szymanskim@datera.pl>)
List pgsql-performance
Michal Szymanski wrote:
> Tom Lane wrote:

> >(For the record, the reason you see nonlinear degradation is the
> >accumulation of tentatively-dead versions of the row, each of which has
> >to be rechecked by each later update.)
> >
> There is another  strange  thing. We  have two versions of our test
> environment one with production DB copy and second genereated with
> minimal data set and it is odd that update presented above on copy of
> production is executing 170ms but on small DB it executing 6s !!!!

How are you vacuuming the tables?

--
Alvaro Herrera                        http://www.advogato.org/person/alvherre
"El conflicto es el camino real hacia la unión"

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