building gist index on int[] field is terrible slow. Is it bug?

On Thu, 16 Aug 2007, Pavel Stehule wrote:

Hello

I tested contrib package intarray and gist support from this package.
I was surpirised. Index building needed lot of time.

10K fields .. 106sec
20K f ..265 sec
30Kf .. 450 sec
50Kf .. 1283sec

building gin index for 50K fields needed 0.5sec

you probably need gist__intbig_ops

Regards
Pavel Stehule

sample of data:
pavel=# select * from test limit 10;
a
-----------------------
{4209,4207,4197,2066}
{4832,3004}
{4629}
{3243}
{4816}
{3726}
{4834}
{1459,3160,3984}
{4569}
{4164,1307,962,4482}
(10 rows)

pavel=# select version();
version
-------------------------------------------------------------------------------------------------------
PostgreSQL 8.3devel on i686-pc-linux-gnu, compiled by GCC gcc (GCC)
4.1.2 20070502 (Red Hat 4.1.2-12)
(1 row)

Time: 442,034 ms

pavel=# show maintenance_work_mem ;
maintenance_work_mem
----------------------
16MB
(1 row)

pavel=# set maintenance_work_mem to '300MB';
SET
Time: 0,230 ms
pavel=#
pavel=# CREATE index fooidx on test using gist(a gist__int_ops);
CREATE INDEX
Time: 1269276,866 ms

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Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83

2007/8/16, Oleg Bartunov <oleg@sai.msu.su>:

On Thu, 16 Aug 2007, Pavel Stehule wrote:

Hello

I tested contrib package intarray and gist support from this package.
I was surpirised. Index building needed lot of time.

10K fields .. 106sec
20K f ..265 sec
30Kf .. 450 sec
50Kf .. 1283sec

building gin index for 50K fields needed 0.5sec

you probably need gist__intbig_ops

yes, it helps
thank you
Pavel Stehule