Re: Overhead cost of Serializable Snapshot Isolation

Поиск
Список
Период
Сортировка
От Heikki Linnakangas
Тема Re: Overhead cost of Serializable Snapshot Isolation
Дата
Msg-id 4E9526DE.6040706@enterprisedb.com
обсуждение исходный текст
Ответ на Re: Overhead cost of Serializable Snapshot Isolation  (Simon Riggs <simon@2ndQuadrant.com>)
Ответы Re: Overhead cost of Serializable Snapshot Isolation
Список pgsql-hackers
On 11.10.2011 23:21, Simon Riggs wrote:
> If the normal default_transaction_isolation = read committed and all
> transactions that require serializable are explicitly marked in the
> application then there is no way to turn off SSI without altering the
> application. That is not acceptable, since it causes changes in
> application behaviour and possibly also performance issues.

I don't get that. If all the transactions that require serializability 
are marked as such, why would you disable SSI for them? That would just 
break the application, since the transactions would no longer be 
serializable.

If they don't actually need serializability, but repeatable read is 
enough, then mark them that way.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: Dumping roles improvements?
Следующее
От: Jeff Davis
Дата:
Сообщение: Re: COUNT(*) and index-only scans