Received: from localhost (unknown [200.46.204.183]) by developer.postgresql.org (Postfix) with ESMTP id AB22B2E013A for ; Wed, 4 Jun 2008 21:46:08 -0300 (ADT) Received: from developer.postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 25792-01-4 for ; Wed, 4 Jun 2008 21:45:52 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by developer.postgresql.org (Postfix) with ESMTP id EB3AC2E00CE for ; Wed, 4 Jun 2008 21:23:52 -0300 (ADT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.2/8.14.2) with ESMTP id m550NHsg007474; Wed, 4 Jun 2008 20:23:17 -0400 (EDT) To: Andrew Dunstan cc: Greg Smith , Andreas Pflug , "Decibel!" , Peter Eisentraut , pgsql-hackers@postgresql.org, Josh Berkus Subject: Re: Overhauling GUCS In-reply-to: <48472E47.7030701@dunslane.net> References: <48409D1E.3070208@agliodbs.com> <200806010032.53337.peter_e@gmx.net> <17932.1212415926@sss.pgh.pa.us> <20080604131810.GH65238@decibel.org> <4846A483.8000001@pse-consulting.de> <29525.1212613052@sss.pgh.pa.us> <48472E47.7030701@dunslane.net> Comments: In-reply-to Andrew Dunstan message dated "Wed, 04 Jun 2008 20:07:35 -0400" Date: Wed, 04 Jun 2008 20:23:17 -0400 Message-ID: <7473.1212625397@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200806/199 X-Sequence-Number: 119312 Andrew Dunstan writes: > Tom Lane wrote: >> * Can we build a "configuration wizard" to tell newbies what settings >> they need to tweak? > That would trump all the other suggestions conclusively. Anyone good at > expert systems? How far could we get with the answers to just three questions: * How many concurrent queries do you expect to have? * How much RAM space are you willing to let Postgres use? * How much "overhead" disk space are you willing to let Postgres use? concurrent queries drives max_connections, obviously, and RAM space would drive shared_buffers and effective_cache_size, and both of them would be needed to size work_mem. The third one is a bit weird but I don't see any other good way to set the checkpoint parameters. If those aren't enough questions, what else must we ask? Or maybe they aren't the right questions at all --- maybe we should ask "is this a dedicated machine or not" and try to extrapolate everything else from what we (hopefully) can find out about the hardware. regards, tom lane