Re: rand48 replacement - Mailing list pgsql-hackers

From Fabien COELHO
Subject Re: rand48 replacement
Date
Msg-id alpine.DEB.2.22.394.2107060805140.3858351@pseudo
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In response to Re: rand48 replacement  (Yura Sokolov <y.sokolov@postgrespro.ru>)
Responses Re: rand48 replacement  (Yura Sokolov <y.sokolov@postgrespro.ru>)
List pgsql-hackers
Hello Yura,

> I believe most "range" values are small, much smaller than UINT32_MAX.
> In this case, according to [1] fastest method is Lemire's one (I'd take
> original version from [2]) [...]

Yep.

I share your point that the range is more often 32 bits.

However, I'm not enthousiastic at combining two methods depending on the 
range, the function looks complex enough without that, so I would suggest 
not to take this option. Also, the decision process adds to the average 
cost, which is undesirable. I would certainly select the unbias multiply 
method if we want a u32 range variant.

-- 
Fabien.



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