Re: Improving GEQO

On Wed, May 27, 2015 at 3:06 PM, boix <boix(at)uclv(dot)cu> wrote:
> Hello, my partner and me are working with the goal of improve the GEQO's
> performance, we tried with Ant Colony Optimization, but it does not improve,
> actually we are trying with a new variant of Genetic Algorithm, specifically
> Micro-GA. This algorithm finds a better solution than GEQO in less time,
> however the total query execution time is higher. The fitness is calculated
> by geqo_eval function. Does anybody know why this happens?
>
> We attach the patch made with the changes in postgresql-9.2.0.

can you submit more details? for example 'explain analyze' (perhaps
here: http://explain.depesz.com/) of the plans generated GEQO vs GA vs
stock? It sounds like you might be facing an estimation miss which is
not really an issue a better planner could solve.

That said, assuming you're getting 'better' plans in less time suggest
you might be on to something.

merlin