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

Поиск
Список
Период
Сортировка
От Junji TERAMOTO
Тема Re: Quick-and-dirty compression for WAL backup blocks
Дата
Msg-id 42A556CA.6030003@lab.ntt.co.jp
обсуждение исходный текст
Ответ на Re: Quick-and-dirty compression for WAL backup blocks  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-hackers
Tom Lane wrote:

>>>>In the XLogInsert(), it makes two kinds of logs, "whole buffer(page)
>>>>log" and "partial buffer log", isn't it?  Is it only "who buffer
>>>>log"
>>>>to generate a log with "hole"?
>
>>
>> Right.

I see.
I think, it is important to reduce the necessities to write whole pages
to WAL (as TODO list).
# It seems difficult to do so... Compressing WAL is easier way.

>> No, because the WAL code cannot assume that all pages follow the
>> convention that pd_lower and pd_upper represent the boundaries of
>> free space.  (As a counterexample: index metapages don't always
>> do that.)

Oh, I forget it.
And I think it is good idea to modify XLogInsert API as CVS, too.

-- 
Junji Teramoto


В списке pgsql-hackers по дате отправления:

Предыдущее
От: "Qingqing Zhou"
Дата:
Сообщение: Re: adding new pages bulky way
Следующее
От: Atsushi Ogawa
Дата:
Сообщение: Re: [PATCHES] regexp_replace