Received: from localhost (unknown [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id DF7C02E37B9 for ; Fri, 14 Dec 2007 07:04:08 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-maia, port 10024) with ESMTP id 28050-05 for ; Fri, 14 Dec 2007 07:03:59 -0400 (AST) Received: from nf-out-0910.google.com (nf-out-0910.google.com [64.233.182.186]) by postgresql.org (Postfix) with ESMTP id 1B72E2E34C1 for ; Fri, 14 Dec 2007 07:04:04 -0400 (AST) Received: by nf-out-0910.google.com with SMTP id f5so775611nfh.23 for ; Fri, 14 Dec 2007 03:04:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:user-agent:mime-version:to:cc:subject:references:in-reply-to:content-type:content-transfer-encoding:sender; bh=b9yLzTD51ZmW4P3UtBFAaumqjyCdQs+EHttRk34OJSw=; b=EExF0Fm2nw8HWLt7Ty6WUXDw0wFYU6K0/jBUgSklFcAXyyB6XCmKH/kIIsZQulD5dQ+Ga1aUNDIfIE2e4vNySDoe14uIBEwTGFE3jMgM/5g1lNZBj/lqsfaYDheMiAj0zYNyRouWbrTZG6kcuWpT77o318A/Ks8bf+nEoKjhzv8= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject:references:in-reply-to:content-type:content-transfer-encoding:sender; b=OQI7Feq6Xy9MiPRvIK8aIZafVz2iN1m5AuodPqKzuUakUFANCORG+96827xHmZZheNpiEypHOmvNul2YOJCHzxtrKgab/PYk6gAGZ1xIFqlnp4Q+SB7Srzz8r+pdqZvvpEInbjxjM3XNuxBfVospvyl9vb3hEIjOMsrxUcCQBE0= Received: by 10.82.145.7 with SMTP id s7mr8539214bud.6.1197630243132; Fri, 14 Dec 2007 03:04:03 -0800 (PST) Received: from ?172.24.32.184? ( [62.232.55.118]) by mx.google.com with ESMTPS id z37sm10575772ikz.2007.12.14.03.04.00 (version=SSLv3 cipher=RC4-MD5); Fri, 14 Dec 2007 03:04:01 -0800 (PST) Message-ID: <4762631C.3050709@enterprisedb.com> Date: Fri, 14 Dec 2007 11:03:56 +0000 From: Heikki Linnakangas User-Agent: Icedove 1.5.0.14pre (X11/20071020) MIME-Version: 1.0 To: "Bebarta, Simanchala" CC: pgsql-performance@postgresql.org Subject: Re: Need help on parameters and their values to tune the postgresql database References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200712/208 X-Sequence-Number: 28024 Bebarta, Simanchala wrote: > I am doing a performance benchmarking test by using benchmarkSQL tool on > postgresql 8.2.4.I need to tune the parameters to achieve an optimal > performance of the postgresql database. > > I have installed postgresql 8.2.4 on RHEL AS4. It is a DELL Optiplex > GX620 PC with 4GB RAM. > > Please suggest me which parameters I need to tune and what would be the > possible values for the parameters. > > Appreciate if I would get a quick response. Why are you doing the benchmark? That's going to have a big impact on how you should tune. For example, how much do you value data integrity, in case of a crash or power outage? How many warehouses are you planning to use? The fact that you didn't mention anything about your I/O hardware suggests that you're planning to do a test that fits entirely in cache. If that's the case, you're going to be limited by the rate you can fsync the commit WAL records to disk. If you don't care about data integrity, you can turn fsync=off, to eliminate that bottleneck. In that case you'll also want to turn full_page_writes=off; that'll reduce the CPU overhead somewhat. Another important factor is how long you're going to run the test. If you run it for more than say 10 minutes, you'll have to run vacuum to keep the table sizes in check. If it's all in memory, as I presume, autovacuum might be enough for the task. PS. You might want to talk to these guys from Unisys: http://www.pgcon.org/2007/schedule/events/16.en.html -- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com