Re: [HACKERS] [WIP] Zipfian distribution in pgbench - Mailing list pgsql-hackers

From Fabien COELHO
Subject Re: [HACKERS] [WIP] Zipfian distribution in pgbench
Date
Msg-id alpine.DEB.2.20.1707171247270.9472@lancre
Whole thread Raw
In response to Re: [HACKERS] [WIP] Zipfian distribution in pgbench  (Alik Khilazhev <a.khilazhev@postgrespro.ru>)
Responses Re: [HACKERS] [WIP] Zipfian distribution in pgbench
List pgsql-hackers
>> Ok, so you did not get the large bias for i=3. Strange.
>
> I got large bias for i=3 and theta > 1 even with a million outcomes,

Ok. So this is similar to what I got.

Is this bias expected from the drawing method, say because it is 
approximated and the approximation is weak at some points, or is there an 
issue with its implementation, says some shift which gets smoothed down 
for higher indexes?

> I am attaching patch v3. Among other things I fixed small typo in 
> description of random_exponential function in pgbench.sgml file.

I'll look into that.

-- 
Fabien.



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