Re: Question about memory allocations

From: Andrew McMillan
Subject: Re: Question about memory allocations
Date: ,
Msg-id: 1176453355.609.4.camel@hippy.mcmillan.net.nz
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In response to: Question about memory allocations  (Steve)
Responses: Re: Question about memory allocations  (Steve)
List: pgsql-performance

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how to efficiently update tuple in many-to-many relationship?  (Drew Wilson, )
 Re: how to efficiently update tuple in many-to-many relationship?  ("Merlin Moncure", )
 Re: how to efficiently update tuple in many-to-many relationship?  (Tom Lane, )
  Re: how to efficiently update tuple in many-to-many relationship?  (Drew Wilson, )
   Re: how to efficiently update tuple in many-to-many relationship?  (Tom Lane, )
    Re: how to efficiently update tuple in many-to-many relationship?  (Drew Wilson, )
     Re: how to efficiently update tuple in many-to-many relationship?  (Tom Lane, )
      Re: how to efficiently update tuple in many-to-many relationship?  (Drew Wilson, )
       Re: how to efficiently update tuple in many-to-many relationship?  (Tom Lane, )
        Question about memory allocations  (Steve, )
         Re: Question about memory allocations  (Tom Lane, )
          Re: Question about memory allocations  (Steve, )
         Re: Question about memory allocations  (Greg Smith, )
          Re: Question about memory allocations  (Steve, )
         Re: Question about memory allocations  (Andrew McMillan, )
          Re: Question about memory allocations  (Steve, )
           Re: Question about memory allocations  (Ron, )
            Re: Question about memory allocations  (Tom Lane, )
           Re: Question about memory allocations  (Carlos Moreno, )
            Re: Question about memory allocations  ("Jan de Visser", )

On Tue, 2007-04-10 at 15:28 -0400, Steve wrote:
>
> I'm trying to tune the memory usage of a new machine that has a -lot- of
> memory in it (32 gigs).

...
>
> shared_buffers = 16GB

Really?

Wow!

Common wisdom in the past has been that values above a couple of hundred
MB will degrade performance.  Have you done any benchmarks on 8.2.x that
show that you get an improvement from this, or did you just take the
"too much of a good thing is wonderful" approach?

Cheers,
                    Andrew.

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