Re: [HACKERS] pow support for pgbench

On Fri, Dec 22, 2017 at 12:46 AM, Raúl Marín Rodríguez
<rmrodriguez@carto.com> wrote:
>> If a double is always returned, I'm wondering whether keeping the ipow
>> version makes much sense: In case of double loss of precision, the precision
>> is lost, too bad, and casting back to int won't bring it back.
>
> I've kept it because knowing that both are ints enables not making a lot of
> checks (done in math.h pow) so it's way faster. In my system it's 2-3ns vs
> ~40ns. I'm willing to settle for using just pow() if that makes it clearer.

This version looks good to me, except that I wonder if we should try
to switch to the floating-point version if the integer version
would/does overflow.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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