Re: sequential scan unduly favored over text search gin index

Поиск
Список
Период
Сортировка
От Tom Lane
Тема Re: sequential scan unduly favored over text search gin index
Дата
Msg-id 4289.1308635599@sss.pgh.pa.us
обсуждение исходный текст
Ответ на Re: sequential scan unduly favored over text search gin index  (Sushant Sinha <sushant354@gmail.com>)
Ответы Re: sequential scan unduly favored over text search gin index
Список pgsql-performance
Sushant Sinha <sushant354@gmail.com> writes:
>> I guess you could poke the planner towards the bitmap scan by lowering
>> the random_page_cost (the default value is 4, I'd say lowering it to 2
>> should do the trick).

> The numbers that I gave was after setting random_page_cost = 1.0 After
> this I don't know what to do.

I think part of the issue here is that the @@ operator is expensive,
and so evaluating it once per row is expensive, but the pg_proc.procost
setting for it doesn't adequately reflect that.  You could experiment
with tweaking that setting ...

            regards, tom lane

В списке pgsql-performance по дате отправления:

Предыдущее
От: Dan Harris
Дата:
Сообщение: Contemplating SSD Hardware RAID
Следующее
От: Greg Smith
Дата:
Сообщение: Re: Contemplating SSD Hardware RAID