Message-ID: <4DEC84D7.7040602@enterprisedb.com>
Date: Mon, 06 Jun 2011 10:42:15 +0300
From: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
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To: Alexander Korotkov <aekorotkov@gmail.com>
CC: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: WIP: Fast GiST index build
References: <BANLkTikgOQ1+r=A9b08szNTeEWsk-cNMMg@mail.gmail.com>
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On 03.06.2011 14:02, Alexander Korotkov wrote:
> Hackers,
>
> WIP patch of fast GiST index build is attached. Code is dirty and comments
> are lacking, but it works. Now it is ready for first benchmarks, which
> should prove efficiency of selected technique. It's time to compare fast
> GiST index build with repeat insert build on large enough datasets (datasets
> which don't fit to cache). There are following aims of testing:
> 1) Measure acceleration of index build.
> 2) Measure change in index quality.
> I'm going to do first testing using synthetic datasets. Everybody who have
> interesting real-life datasets for testing are welcome.

I ran another test with a simple table generated with:

CREATE TABLE pointtest (p point);
INSERT INTO pointtest SELECT point(random(), random()) FROM 
generate_series(1,50000000);

Generating a gist index with:

CREATE INDEX i_pointtest ON pointtest USING gist (p);

took about 15 hours without the patch, and 2 hours with it. That's quite 
dramatic.

-- 
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com