Re: Simple postgresql.conf wizard

Поиск
Список
Период
Сортировка
От Mark Wong
Тема Re: Simple postgresql.conf wizard
Дата
Msg-id 70c01d1d0811141126h149b17f6m6d460944f6d890b2@mail.gmail.com
обсуждение исходный текст
Ответ на Re: Simple postgresql.conf wizard  (Tom Lane <tgl@sss.pgh.pa.us>)
Ответы Re: Simple postgresql.conf wizard  (Bruce Momjian <bruce@momjian.us>)
Список pgsql-hackers
On Thu, Nov 13, 2008 at 11:53 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Heikki Linnakangas <heikki.linnakangas@enterprisedb.com> writes:
>> A lot of people have suggested raising our default_statistics target,
>> and it has been rejected because there's some O(n^2) behavior in the
>> planner, and it makes ANALYZE slower, but it's not that crazy.
>
> I think everyone agrees it ought to be raised.  Where the rubber meets
> the road is deciding just *what* to raise it to.  We've got no
> convincing evidence in favor of any particular value.
>
> If someone actually wanted to put some effort into this, I'd suggest
> taking some reasonably complex benchmark (maybe TPCH or one of the DBT
> series) and plotting planner runtime for each query as a function of
> statistics_target, taking care to mark the breakpoints where it shifted
> to a better (or worse?) plan due to having better stats.

Almost there...  I have a MSA70 plugged into the DL380 I have from HP
and I'm trying to find time to get my scripts updated to deal with how
tools have changed over the years...  I'm updating the DBT-2 (tpc-c
kit) I have first

Regards,
Mark


В списке pgsql-hackers по дате отправления:

Предыдущее
От: "hernan gonzalez"
Дата:
Сообщение: Re: Column reordering in pg_dump
Следующее
От: Tom Lane
Дата:
Сообщение: Re: Assorted contrib infrastructures patch