Re: [GENERAL] Performance of full outer join in 8.3 - Mailing list pgsql-hackers

From Hannu Krosing
Subject Re: [GENERAL] Performance of full outer join in 8.3
Date
Msg-id 1240051850.7401.7.camel@huvostro
Whole thread Raw
In response to Re: [GENERAL] Performance of full outer join in 8.3  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: [GENERAL] Performance of full outer join in 8.3
List pgsql-hackers
On Wed, 2009-04-15 at 18:04 -0400, Tom Lane wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
> > I've always been scared to ask this question, in case the answer is No,
> > but: Do we have a set of regression tests for the optimizer anywhere?
> 
> Nothing beyond what is in the standard tests.  While that's okay at
> catching wrong answers --- and we have memorialized a number of such
> issues in the tests --- the framework is not good for catching things
> that run slower than they ought.

Can't we make first cut at it by just running with timings on and then
compare ratios of running times - maybe with 2-3X tolerance - to catch
most obvious regressions ?

>             regards, tom lane

-- 
Hannu Krosing   http://www.2ndQuadrant.com
PostgreSQL Scalability and Availability   Services, Consulting and Training



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