R-Tree implementation using GiST

Hi,

I've put R-Tree realization using GiST (yet another test of our changes in
gist code )on my gist page http://www.sai.msu.su/~megera/postgres/gist/
Also, I've put some GiST related papers for interested readers.
The package( contrib-rtree_box_gist.tar.gz ) is built for 7.1.
If you find it's interesting you may include it into contrib area for 7.1

from README.rtree_box_gist:

1. One interesting thing is that insertion time for built-in R-Tree is
about 8 times more than ones for GiST implementation of R-Tree !!!
2. Postmaster requires much more memory for built-in R-Tree
3. Search time depends on dataset. In our case we got:
+------------+-----------+--------------+
|Number boxes|R-tree, sec|R-tree using |
| | | GiST, sec |
+------------+-----------+--------------+
| 10| 0.002| 0.002|
+------------+-----------+--------------+
| 100| 0.002| 0.002|
+------------+-----------+--------------+
| 1000| 0.002| 0.002|
+------------+-----------+--------------+
| 10000| 0.015| 0.025|
+------------+-----------+--------------+
| 20000| 0.029| 0.048|
+------------+-----------+--------------+
| 40000| 0.055| 0.092|
+------------+-----------+--------------+
| 80000| 0.113| 0.178|
+------------+-----------+--------------+
| 160000| 0.338| 0.337|
+------------+-----------+--------------+
| 320000| 0.674| 0.673|
+------------+-----------+--------------+

Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83