Re: qsort again (was Re: [PERFORM] Strange Create

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От Tom Lane
Тема Re: qsort again (was Re: [PERFORM] Strange Create
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Msg-id 28768.1140106823@sss.pgh.pa.us
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Ответ на Re: qsort again (was Re: [PERFORM] Strange Create  (Ron <rjpeace@earthlink.net>)
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Ron <rjpeace@earthlink.net> writes:
> Your cost comment basically agrees with mine regarding the cost of
> random memory accesses.  The good news is that the number of datums
> to be examined during the pivot choosing process is small enough that
> the datums can fit into CPU cache while the pointers to them can be
> assigned to registers: making pivot choosing +very+ fast when done correctly.

This is more or less irrelevant given that comparing the pointers is not
the operation we need to do.

            regards, tom lane

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