On Mon, Feb 06, 2012 at 04:19:07PM -0500, Bruce Momjian wrote:
> Peter Geoghegan obviously has done some serious work in improving
> sorting, and worked well with the community process. He has done enough
> analysis that I am hard-pressed to see how we would get similar
> improvement using a different method, so I think it comes down to
> whether we want the 28% speedup by adding 55k (1%) to the binary.
>
> I think Peter has shown us how to get that, and what it will cost --- we
> just need to decide now whether it is worth it. What I am saying is
> there probably isn't a cheaper way to get that speedup, either now or in
> the next few years. (COPY might need similar help for speedups.)
>
> I believe this is a big win and well worth the increased binary size
> because the speed up is significant, and because it is of general
> usefulness for a wide range of queries. Either of these would be enough
> to justify the additional 1% size, but both make it an easy decision for
> me.
>
> FYI, I believe COPY needs similar optimizations; we have gotten repeated
> complaints about its performance and this method of optmization might
> also be our only option.
Sorry, that was wordy. What I am saying is that years ago we did
hot-spot optimization for storage and tuple access using macros. We
have looked for cheap optimizations for sort (and COPY) for years, but
haven't found it. If we want optimizations in these areas, we are
probably going to need to do the same sort of hot-spot optimization we
did earlier, and Peter's work is an excellent candidate for that.
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://enterprisedb.com
+ It's impossible for everything to be true. +