Re: log_duration is redundant, no?

Поиск
Список
Период
Сортировка
От Guillaume Smet
Тема Re: log_duration is redundant, no?
Дата
Msg-id 1d4e0c10609071550x5701b926te018649d77bf399f@mail.gmail.com
обсуждение исходный текст
Ответ на Re: log_duration is redundant, no?  (Bruce Momjian <bruce@momjian.us>)
Список pgsql-hackers
On 9/8/06, Bruce Momjian <bruce@momjian.us> wrote:
> If you are using an external tool, can't you just restrict what you
> display based on the logged duration?

It's not a matter of having too much information in our reports (the
more information I have, the happier I am :)). It's a matter of
slowing down too much the server with too much I/O.
We can afford to log every duration and queries slower than 500ms
nearly without any overhead. We can't afford to log every query, it
generates too much I/O - note that we tried to do it and it was really
too slow.
With the former configuration we log 1.2 GB/day, with the latter I
suspect it will be far more than 60 GB/day (I don't have the exact
number as we can't do it for real but queries slower than 500 ms
represents 1/100 of the total amount of queries).

Query logging is really a nice way to monitor the activity of a
PostgreSQL server and the overhead is not that high if logging I/O are
not too intensive.

--
Guillaume


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: log_duration is redundant, no?
Следующее
От: Bruce Momjian
Дата:
Сообщение: Re: log_duration is redundant, no?