Re: Yet another fast GiST build

At Wed, 16 Sep 2020 12:27:09 +0500, "Andrey M. Borodin" <x4mmm@yandex-team.ru> wrote in 
> I was thinking that machine epsilon is near 1e-300, but I was
> wrong. It's actually near 1e-15.

FWIW, the mantissa of double is effectively 52+1 bits, about 15.9
digits. so 1+(1e-16) is basically indistincitve from
1+(2e-16). Actually two double precisions 1+2e-16 and 1+3e-16 are
indistinctive from each other.

> Actually, I just want to understand what changes between v18 and v19 changed on-page order of items. I look into
patchdiff and cannot figure it out. There are only logging changes. How this affects scan?
 

FWIW, I saw the same symptom by my another patch after adding a value
to POINT_TBL. (But I didn't pursue the cause further..)

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center