Re: Abbreviated keys for text cost model fix

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От Peter Geoghegan
Тема Re: Abbreviated keys for text cost model fix
Дата
Msg-id CAM3SWZTYVuaWG5gR3tpE9eRigpi78TFs0T9FJmYisX9pBM=eRw@mail.gmail.com
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Ответ на Re: Abbreviated keys for text cost model fix  (Jeremy Harris <jgh@wizmail.org>)
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On Tue, Mar 3, 2015 at 2:00 AM, Jeremy Harris <jgh@wizmail.org> wrote:
> Yes; there seemed no advantage to any additional complexity.
> The merge consistently performs fewer comparisons than the
> quicksort, on random input - and many fewer if there are
> any sorted (or reverse-sorted) sections.  However, it also
> consistently takes slightly longer (a few percent).  I was
> unable to chase this down but assume it to be a cacheing
> effect.  So I don't currently think it should replace the
> current sort for all use.

It's definitely caching effects. That's a very important consideration here.

-- 
Peter Geoghegan



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