Re: [Testperf-general] Re: First set of OSDL Shared Memscalability

Поиск
Список
Период
Сортировка
От Bruce Momjian
Тема Re: [Testperf-general] Re: First set of OSDL Shared Memscalability
Дата
Msg-id 200410151657.i9FGvZQ13745@candle.pha.pa.us
обсуждение исходный текст
Ответ на Re: [Testperf-general] Re: First set of OSDL Shared Memscalability results, some wierdness ...  (Tom Lane <tgl@sss.pgh.pa.us>)
Ответы Re: [Testperf-general] Re: First set of OSDL Shared Memscalability results, some wierdness ...  ("Simon Riggs" <simon@2ndquadrant.com>)
Список pgsql-performance
Tom Lane wrote:
> > I've been thinking about implementing a scheme that helps you decide how
> > big the shared_buffers SHOULD BE, by making the LRU list bigger than the
> > cache itself, so you'd be able to see whether there is beneficial effect in
> > increasing shared_buffers.
>
> ARC already keeps such a list --- couldn't you learn what you want to
> know from the existing data structure?  It'd be fairly cool if we could
> put out warnings "you ought to increase shared_buffers" analogous to the
> existing facility for noting excessive checkpointing.

Agreed.  ARC already keeps a list of buffers it had to push out recently
so if it needs them again soon it knows its sizing of recent/frequent
might be off (I think).  Anyway, such a log report would be super-cool,
say if you pushed out a buffer and needed it very soon, and the ARC
buffers are already at their maximum for that buffer pool.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

В списке pgsql-performance по дате отправления:

Предыдущее
От: Richard_D_Levine@raytheon.com
Дата:
Сообщение: Does PostgreSQL run with Oracle?
Следующее
От: Bruce Momjian
Дата:
Сообщение: Re: Does PostgreSQL run with Oracle?