Re: Performance under contention

Список
Период
Сортировка
От Ivan Voras
Тема Re: Performance under contention
Дата
Msg-id iccjub$bn0$1@dough.gmane.org
обсуждение исходный текст
Ответ на Re: Performance under contention  ("Kevin Grittner")
Ответы Re: Performance under contention  (Jignesh Shah)
Re: Performance under contention  ("Kevin Grittner")
Список pgsql-performance
Дерево обсуждения
Performance under contention  (Ivan Voras, )
 Re: Performance under contention  ("Kevin Grittner", )
  Re: Performance under contention  (Ivan Voras, )
   Re: Performance under contention  (Jignesh Shah, )
    Re: Performance under contention  (Omar Kilani, )
   Re: Performance under contention  ("Kevin Grittner", )
    Re: Performance under contention  (Ivan Voras, )
     Re: Performance under contention  (Craig Ringer, )
      Re: Performance under contention  (Ivan Voras, )
      Re: Performance under contention  (Vitalii Tymchyshyn, )
       Re: Performance under contention  ("Kevin Grittner", )
 Re: Performance under contention  ("Kevin Grittner", )
  Re: Performance under contention  (Ivan Voras, )
 Re: Performance under contention  (Greg Smith, )
  Re: Performance under contention  (Ivan Voras, )
 Re: Performance under contention  (Robert Haas, )
  Re: Performance under contention  (Robert Haas, )
  Re: Performance under contention  (Jignesh Shah, )
   Re: Performance under contention  (Jignesh Shah, )
   Re: Performance under contention  (Robert Haas, )
    Re: Performance under contention  (Tom Lane, )
     Re: Performance under contention  (Dave Crooke, )
     Re: Performance under contention  (Robert Haas, )
    Re: Performance under contention  (Ivan Voras, )
     Re: Performance under contention  (Robert Haas, )
      Re: Performance under contention  (Ivan Voras, )
      Re: Performance under contention  (Віталій Тимчишин, )
       Re: Performance under contention  (Ivan Voras, )
       Re: Performance under contention  (Robert Haas, )
        Re: Performance under contention  (Robert Haas, )
         Re: Performance under contention  (Tom Lane, )
          Re: Performance under contention  (Robert Haas, )
           Re: Performance under contention  (Tom Lane, )
            Re: Performance under contention  (Robert Haas, )
On 11/22/10 02:47, Kevin Grittner wrote:
> Ivan Voras  wrote:
>
>> After 16 clients (which is still good since there are only 12
>> "real" cores in the system), the performance drops sharply
>
> Yet another data point to confirm the importance of connection
> pooling.  :-)

I agree, connection pooling will get rid of the symptom. But not the
underlying problem. I'm not saying that having 1000s of connections to
the database is a particularly good design, only that there shouldn't be
a sharp decline in performance when it does happen. Ideally, the
performance should remain the same as it was at its peek.

I've been monitoring the server some more and it looks like there are
periods where almost all servers are in the semwait state followed by
periods of intensive work - approximately similar to the "thundering
herd" problem, or maybe to what Josh Berkus has posted a few days ago.


В списке pgsql-performance по дате отправления:

Предыдущее
От: Jignesh Shah
Дата:
Сообщение: Re: Performance under contention
Следующее
От: kuopo
Дата:
Сообщение: Re: autovacuum blocks the operations of other manual vacuum