Re: ECPG FETCH readahead

Поиск
Список
Период
Сортировка
От Michael Meskes
Тема Re: ECPG FETCH readahead
Дата
Msg-id 20120416160448.GA9968@feivel.credativ.lan
обсуждение исходный текст
Ответ на Re: ECPG FETCH readahead  (Boszormenyi Zoltan <zb@cybertec.at>)
Ответы Re: ECPG FETCH readahead  (Boszormenyi Zoltan <zb@cybertec.at>)
Список pgsql-hackers
On Mon, Apr 16, 2012 at 06:24:57AM +0200, Boszormenyi Zoltan wrote:
> Yes, just like when the readahead window set to 256, FETCH 1024
> will iterate through 4 windows or FETCH 64 iterates through the
> same window 4 times. This is the idea behind the "readahead window".

Really? It's definitely not the idea behind FETCH 1024. Using the same window 4
times for FETCH 64 is the idea though, I agree.

> How about allowing the readahead window to be resized for the
> non-decorated case if the runtime encounters FETCH N and N is
> greater than the previous window?

To be resized by what? IMO a FETCH N should always be a FETCH N, no matter
what, i.e. if the readahead window is larger, use it, but even if it's smaller
we should still fetch N at the same time.

Michael

--
Michael Meskes
Michael at Fam-Meskes dot De, Michael at Meskes dot (De|Com|Net|Org)
Michael at BorussiaFan dot De, Meskes at (Debian|Postgresql) dot Org
Jabber: michael.meskes at googlemail dot com
VfL Borussia! Força Barça! Go SF 49ers! Use Debian GNU/Linux, PostgreSQL


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Merlin Moncure
Дата:
Сообщение: Re: JSON for PG 9.2
Следующее
От: Hannu Krosing
Дата:
Сообщение: Re: JSON for PG 9.2