Received: from localhost (maia-3.hub.org [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id 194AD9FB858 for ; Thu, 12 Apr 2007 23:50:13 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-maia, port 10024) with ESMTP id 98670-03 for ; Thu, 12 Apr 2007 23:50:01 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from westnet.com (westnet.com [216.187.52.2]) by postgresql.org (Postfix) with ESMTP id AA1879FB850 for ; Thu, 12 Apr 2007 23:50:07 -0300 (ADT) Received: from westnet.com (localhost [127.0.0.1]) by westnet.com (8.14.0/8.14.0) with ESMTP id l3D2o8pG001485 for ; Thu, 12 Apr 2007 22:50:08 -0400 (EDT) Received: from localhost (gsmith@localhost) by westnet.com (8.14.0/8.13.2/Submit) with ESMTP id l3D2o8fW001482 for ; Thu, 12 Apr 2007 22:50:08 -0400 (EDT) X-Authentication-Warning: westnet.com: gsmith owned process doing -bs Date: Thu, 12 Apr 2007 22:50:08 -0400 (EDT) From: Greg Smith X-X-Sender: gsmith@westnet.com To: pgsql-performance@postgresql.org Subject: Re: Question about memory allocations In-Reply-To: Message-ID: References: <233A9987-ABA5-4491-A304-FDA1F8FCD962@gmail.com> <14019.1176155022@sss.pgh.pa.us> <22512E5C-A60F-43E7-A370-257F7AF956FD@gmail.com> <16374.1176171185@sss.pgh.pa.us> <25200.1176213242@sss.pgh.pa.us> <26925.1176221294@sss.pgh.pa.us> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200704/286 X-Sequence-Number: 24163 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