Re: Cube Index Size - Mailing list pgsql-hackers

From Teodor Sigaev
Subject Re: Cube Index Size
Date
Msg-id 4DE632B0.5030603@sigaev.ru
Whole thread Raw
In response to Re: Cube Index Size  (Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>)
Responses Re: Cube Index Size
List pgsql-hackers
> Ok, I can reproduce the issue with that. The index is only 4MB in size
> when I populate it with random data (vs. 15 MB with your data). The
> command I used is:
>
> INSERT INTO cubtest SELECT cube(random(), random()) FROM
> generate_series(1,20000);
>
> My guess is that the picksplit algorithm performs poorly with that data.
> Unfortunately, I have no idea how to improve that.

One of idea is add sorting of Datums to be splitted by cost of insertion. It's 
implemented in intarray/tsearch GiST indexes.

Although I'm not sure that it will help but our researches on Guttman's 
picksplit algorimth show significant improvements.
-- 
Teodor Sigaev                                   E-mail: teodor@sigaev.ru
  WWW: http://www.sigaev.ru/
 


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