Re: Hash index todo list item

On Thu, Sep 20, 2007 at 05:12:45PM -0700, Tom Raney wrote:
> We are pleased to announce an upcoming patch to the hash index code
> which improves build time and index size, based on this item in the
> TODO list:
> During index creation, pre-sort the tuples to improve build speed
> http://archives.postgresql.org/pgsql-hackers/2007-03/msg01199.php
>
> Using our implementation, build times and index sizes are
> comparable with btree index build times and index sizes.
> For example, for a particular 12 million row relation, the
> 8.2.4 release requires over 2.8 hours to build the hash index. With our 
> patch, the index is built in 80 seconds.
> Here is the link for a graph, showing a comparative analysis of
> btree and hash index builds and describing the benchmark data.
> http://web.cecs.pdx.edu/~raneyt/pg/
>
> We are currently cleaning up the patch and will submit it asap.
>
> Regards,
> Shreya Bhargava <shreya_bhargav@yahoo.com>
> Tom Raney <twraney@comcast.net>
>

That is super! (and timely)

I was just looking at that some myself since the large index build
times make testing a very laborious process. I am looking forward to
seeing the details. 

Regards,
Ken