Message-ID: <4E72197B.9040602@enterprisedb.com>
Date: Thu, 15 Sep 2011 18:27:55 +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: Double sorting split patch
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On 11.09.2011 22:30, Alexander Korotkov wrote:
> Hackers,
>
> I've got my patch with double sorting picksplit impementation for GiST into
> more acceptable form. A little of testing is below. Index creation time is
> slightly higher, but search is much faster. The testing datasets were
> following:
> 1) uniform dataset - 10M rows
> 2) geonames points - 7.6M rows

I've looked at the patch, and took a brief look at the paper - but I 
still don't understand the algorithm. I just can't get my head around 
the concepts of split pairs and left/right groups. Can you explain that 
in layman's terms? Perhaps an example would help?

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