Re: Question about memory allocations - Mailing list pgsql-performance

From Greg Smith
Subject Re: Question about memory allocations
Date
Msg-id Pine.GSO.4.64.0704122238580.29657@westnet.com
Whole thread Raw
In response to Question about memory allocations  (Steve <cheetah@tanabi.org>)
Responses Re: Question about memory allocations  (Steve <cheetah@tanabi.org>)
List pgsql-performance
On Tue, 10 Apr 2007, Steve wrote:

> - I've set up a configuration (I'll show important values below), and I"m
> wondering if there's any way I can actually see the distribution of memory in
> the DB and how the memory is being used.

I didn't notice anyone address this for you yet.  There is a tool in
contrib/pg_buffercache whose purpose in life is to show you what the
shared buffer cache has inside it.  The documentation in that directory
leads through installing it.  The additional variable you'll likely never
know is what additional information is inside the operating system's
buffer cache.

> # Leaving this low makes the DB complain, but I'm not sure what's #
> reasonable.
> checkpoint_segments = 128

That's a reasonable setting for a large server.  The main downside to
setting it that high is longer recovery periods after a crash, but I doubt
that's a problem for you if you're so brazen as to turn off fsync.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD

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