AW: [HACKERS] Some notes on optimizer cost estimates

Поиск
Список
Период
Сортировка
От Zeugswetter Andreas SB
Тема AW: [HACKERS] Some notes on optimizer cost estimates
Дата
Msg-id 219F68D65015D011A8E000006F8590C603FDC21C@sdexcsrv1.f000.d0188.sd.spardat.at
обсуждение исходный текст
Ответы Re: AW: [HACKERS] Some notes on optimizer cost estimates  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: AW: [HACKERS] Some notes on optimizer cost estimates  (Peter Eisentraut <peter_e@gmx.net>)
Список pgsql-hackers
> > Couldn't we test some of these parameters inside configure and set
> > them there?
> 
> If we could figure out a reasonably cheap way of estimating these
> numbers, it'd be worth setting up custom values at installation time.

Imho this whole idea is not so good. (Sorry)

My points are:
1. even if it is good for an optimizer to be smart,it is even more important, that it is predictable
2. I compile on test machine, production is completely different(more processors, faster disks and controllers)

Andreas


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: [HACKERS] Well, then you keep your darn columns
Следующее
От: Patrick Welche
Дата:
Сообщение: Re: [HACKERS] Re: pg_dump possible fix, need testers.