Re: [GENERAL] shared_buffers smaller than max_wal_size

Поиск
Список
Период
Сортировка
От Tomas Vondra
Тема Re: [GENERAL] shared_buffers smaller than max_wal_size
Дата
Msg-id 282731b1-15dc-c36d-9470-89b142b096cd@2ndquadrant.com
обсуждение исходный текст
Ответ на Re: [GENERAL] shared_buffers smaller than max_wal_size  (Vladimir Mihailenco <vladimir.webdev@gmail.com>)
Ответы Re: [GENERAL] shared_buffers smaller than max_wal_size  (Vladimir Mihailenco <vladimir.webdev@gmail.com>)
Список pgsql-general
On 09/24/2017 11:03 AM, Vladimir Mihailenco wrote:
> Thanks for your response. Ss I understand it now the difference is
> that checkpoints are synchronous but dirty pages eviction from shared
> buffers are asynchronous, correct? How then Postgres ensures that OS
> writes data to the disk so WAL can be deleted?
> 

The last step in a checkpoin is fsync() on the files. Without that, the
checkpoint is considered incomplete and the database won't rely on it.


regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


-- 
Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general

В списке pgsql-general по дате отправления:

Предыдущее
От: Vladimir Mihailenco
Дата:
Сообщение: Re: [GENERAL] shared_buffers smaller than max_wal_size
Следующее
От: hvjunk
Дата:
Сообщение: [GENERAL] "alter table...if exists... add bigserial "still adds extra sequence