Re: Abbreviated keys for Numeric (was: Re: B-Tree support function number 3 (strxfrm() optimization)) - Mailing list pgsql-hackers

On Fri, Feb 20, 2015 at 1:33 PM, Tomas Vondra
<tomas.vondra@2ndquadrant.com> wrote:
> For example with the same percentile_disc() test as in the other thread:
>
>    create table stuff as select random()::numeric as randnum
>                            from generate_series(1,1000000);
>
>    analyze stuff;
>
>    select percentile_disc(0) within group (order by randnum) from stuff;
>
>
> I get pretty much no difference in runtimes (not even for the smallest
> dataset, where the Datum patch speedup was significant).
>
> What am I doing wrong?

So you're testing both the patches (numeric + datum tuplesort) at the same time?

I can't think why this would make any difference. Did you forget to
initdb, so that the numeric sortsupport routine was used?

-- 
Peter Geoghegan