On Mon, Jan 30, 2012 at 1:39 AM, Jeff Davis <pg...@j-davis.com> wrote:
> Thank you for the updates. I have a small patch attached. > > The only code change I made was very minor: I changed the constants used > in the penalty function because your version used INFINITE_BOUND_PENALTY > when adding an empty range, and that didn't quite make sense to me. If > I'm mistaken you can leave it as-is. > > I also attached range-gist-test.sql, which I used for a performance > test. I mix various types of ranges together in a larger table of 1.1M > tuples. And then I create a smaller table that only contains normal > ranges and empty ranges. There are two tests: > 1. Create an index on the big table > 2. Do a "range join" (using "overlaps" rather than "equals") where the > smaller table is on the outer side of a nested loop join and an index > scan over the larger table on the inner. > > The index creation time reduces by a small amount with the patch, from > around 16s without the patch to around 13s with the patch. The query > time, however, dropped from around 26s to around 14s! Almost 2x speedup > with the patch! > > Moreover, looking at the loop timing in the explain analyze output, it > goes from about "7..24" ms per loop down to about "1.5..13" ms per loop. > That seems to indicate that the index distribution is better, with more > queries returning quickly. > > So, great work Alexander! Very convincing results. > Great! Thank you for reviewing this patch! > Marking "ready for committer", but please apply my comment fixes at your > discretion. > Patch with your comment fixes is attached. ----- With best regards, Alexander Korotkov.
rangetypegist-0.7.patch.gz
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