Re: Slow Postgresql server

От: Guido Neitzer
Тема: Re: Slow Postgresql server
Дата: ,
Msg-id: 340C0645-B8F0-4691-B254-76DED649C8D9@event-s.net
(см: обсуждение, исходный текст)
Ответ на: Re: Slow Postgresql server  (Jason Lustig)
Список: pgsql-performance

Скрыть дерево обсуждения

Slow Postgresql server  (Jason Lustig, )
 Re: Slow Postgresql server  (Dennis Bjorklund, )
 Re: Slow Postgresql server  (Jeff Frost, )
 Re: Slow Postgresql server  (Ron, )
  Re: Slow Postgresql server  (Guido Neitzer, )
   Re: Slow Postgresql server  (Ron, )
    Re: Slow Postgresql server  (Guido Neitzer, )
     Re: Slow Postgresql server  (Scott Marlowe, )
      Re: Slow Postgresql server  (Jeff Frost, )
       Re: Slow Postgresql server  (Carlos Moreno, )
       Strangely Variable Query Performance  (Steve, )
        Re: Strangely Variable Query Performance  (Tom Lane, )
         Re: Strangely Variable Query Performance  (Steve, )
          Re: Strangely Variable Query Performance  (Tom Lane, )
           Re: Strangely Variable Query Performance  (Steve, )
            Re: Strangely Variable Query Performance  (Tom Lane, )
             Re: Strangely Variable Query Performance  (Steve, )
        Re: Strangely Variable Query Performance  (Scott Marlowe, )
         Re: Strangely Variable Query Performance  (Steve, )
          Re: Strangely Variable Query Performance  (Scott Marlowe, )
           Re: Strangely Variable Query Performance  (Steve, )
           Re: Strangely Variable Query Performance  (Tom Lane, )
            Re: Strangely Variable Query Performance  (Steve, )
             Re: Strangely Variable Query Performance  (Tom Lane, )
              Re: Strangely Variable Query Performance  (Steve, )
             Re: Strangely Variable Query Performance  (Tom Lane, )
              Re: Strangely Variable Query Performance  (Steve, )
               Re: Strangely Variable Query Performance  (Tom Lane, )
                Re: Strangely Variable Query Performance  (Steve, )
                 Re: Strangely Variable Query Performance  (Tom Lane, )
                  Re: Strangely Variable Query Performance  (Steve, )
                   Re: Strangely Variable Query Performance  (Tom Lane, )
                   Re: Strangely Variable Query Performance  (Tom Lane, )
                    Re: Strangely Variable Query Performance  (Steve, )
                     Re: Strangely Variable Query Performance  (Tom Lane, )
                      Fwd: Strangely Variable Query Performance  ("Robins Tharakan", )
                     choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Tom Lane, )
                      Re: [HACKERS] choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Alvaro Herrera, )
                       Re: [HACKERS] choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Tom Lane, )
                       Re: [HACKERS] choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Tom Lane, )
              Re: Strangely Variable Query Performance  (Steve, )
             Re: [HACKERS] choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Tom Lane, )
 Re: Slow Postgresql server  (Jeff Frost, )
  Re: Slow Postgresql server  (Jason Lustig, )
   Re: Slow Postgresql server  (Guido Neitzer, )
 Fwd: Strangely Variable Query Performance  (Robins, )
  Re: Fwd: Strangely Variable Query Performance  (Tom Lane, )

On 12.04.2007, at 15:58, Jason Lustig wrote:

> Wow! That's a lot to respond to. Let me go through some of the
> ideas... First, I just turned on autovacuum, I forgot to do that.
> I'm not seeing a major impact though. Also, I know that it's not
> optimal for a dedicated server.

Hmm, why not? Have you recently vacuumed your db manually so it gets
cleaned up? Even a vacuum full might be useful if the db is really
bloated.

> It's not just for postgres, it's also got our apache server on it.
> We're just getting started and didn't want to make the major
> investment right now in getting the most expensive server we can get

Hmmm, but more RAM would definitely make sense, especially in that
szenaria. It really sounds like you machine is swapping to dead.

What does the system say about memory usage?

> Some of the queries are definitely making an impact on the speed.
> We are constantly trying to improve performance, and part of that
> is reassessing our indexes and denormalizing data where it would
> help. We're also doing work with memcached to cache the results of
> some of the more expensive operations.

Hmmm, that kills you even more, as it uses RAM. I really don't think
at the moment that it has something to do with PG itself, but with
not enough memory for what you want to achieve.

What perhaps helps might be connection pooling, so that not so many
processes are created for the requests. It depends on your "middle-
ware" what you can do about that. pg_pool might be an option.

cug




В списке pgsql-performance по дате сообщения:

От: Steve
Дата:
Сообщение: Re: Question about memory allocations
От: Tom Lane
Дата:
Сообщение: Re: Strangely Variable Query Performance