Hello!
I've following project proposal.
Currently GiST index don't have any bulk load functionality. It have to create new index by entry insertion one by one. This makes new index creation relatively slow.
There are various works in computer science about bulk operation on R-tree. Since gist in basic is generalization of R-tree, some of them seems to be applicable to GiST.
Following work seems to be most applicable to GiST:
"Efficient Bulk Operations on Dynamic R-Trees", L. Arge, K. H. Hinrichs, J. Vahrenhold and J. S. Vitter
I believe that implementation of methods of this work should allow to significally reduce GiST index creation time (probably, it'll be possible to achive acceleration of other operations too). Also, it's possible to achive some results in computer science, since GiST is more general data structure than R-tree.
I'm going to create wiki page for this project proposal soon.
I'm last year phd. student and I would like to participate in GSoC with PostgreSQL. I would be especially happy to work with project above or other project related to indexing.
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With best regards,
Alexander Korotkov.