Re: Quick-and-dirty compression for WAL backup blocks

Поиск
Список
Период
Сортировка
От Alvaro Herrera
Тема Re: Quick-and-dirty compression for WAL backup blocks
Дата
Msg-id 20050601142432.GA23593@surnet.cl
обсуждение исходный текст
Ответ на Re: Quick-and-dirty compression for WAL backup blocks  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-hackers
On Wed, Jun 01, 2005 at 10:12:34AM -0400, Tom Lane wrote:
> "Mark Cave-Ayland" <m.cave-ayland@webbased.co.uk> writes:
> > I also noticed your comment above that mentioned that compression would be
> > less effective as the pages became more full. Would changing the loading
> > factor of database pages have an effect here, as I would have thought that
> > the WAL would be fsync'd more aggressively than the heap?
> 
> Yeah, it's predictable that leaving more free space per page would make
> the optimization more effective.

But it would also increase the number of pages, so maybe there would
have to be block dumps more often, which may make the whole thing worse
on average.

-- 
Alvaro Herrera (<alvherre[a]surnet.cl>)
"La realidad se compone de muchos sueños, todos ellos diferentes,
pero en cierto aspecto, parecidos..." (Yo, hablando de sueños eróticos)


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: NOLOGGING option, or ?
Следующее
От: "Brusser, Michael"
Дата:
Сообщение: fdatasync failed, I/O error