Re: Small improvement to compactify_tuples

From: Peter Geoghegan <pg(at)bowt(dot)ie>
To: Юрий Соколов <funny(dot)falcon(at)gmail(dot)com>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Sokolov Yura <funny(dot)falcon(at)postgrespro(dot)ru>, Claudio Freire <klaussfreire(at)gmail(dot)com>, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>, Heikki Linnakangas <hlinnaka(at)iki(dot)fi>, PostgreSQL-Dev <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Small improvement to compactify_tuples
Date: 2017-11-04 23:35:59
Message-ID: 20171104233559.GA8580@marmot
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Юрий Соколов <funny(dot)falcon(at)gmail(dot)com> wrote:
>tps is also reflects changes:
>~17ktps with qsort
>~19ktps with bucket sort
>
>Also vacuum of benchmark's table is also improved:
>~3s with qsort,
>~2.4s with bucket sort

One thing that you have to be careful with when it comes to our qsort
with partially presored inputs is what I like to call "banana skin
effects":

https://postgr.es/m/CAH2-WzkU2xK2dpZ7N8-A1MvuUTTUvhqkfnA+eUtwNwCtgyCJgw@mail.gmail.com

This may have nothing at all to do with your results; I'm just pointing
it out as a possibility.

--
Peter Geoghegan

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Haas 2017-11-05 00:05:59 Re: [POC] Faster processing at Gather node
Previous Message Юрий Соколов 2017-11-04 23:07:33 Re: Small improvement to compactify_tuples