Received: from localhost (unknown [200.46.204.183]) by developer.postgresql.org (Postfix) with ESMTP id 4C4422E0068 for ; Tue, 17 Jun 2008 12:43:26 -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 42236-04-3 for ; Tue, 17 Jun 2008 12:43:21 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from rv-out-0506.google.com (rv-out-0506.google.com [209.85.198.234]) by developer.postgresql.org (Postfix) with ESMTP id DE8652E0074 for ; Tue, 17 Jun 2008 12:42:35 -0300 (ADT) Received: by rv-out-0506.google.com with SMTP id b25so6482824rvf.43 for ; Tue, 17 Jun 2008 08:42:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:cc:in-reply-to:mime-version:content-type :content-transfer-encoding:content-disposition:references; bh=pNFr+NQ8kKHirPGoIiXUGBLOvWJ78Xs0oxZq45saro4=; b=azo6WPNdu+iKduza2LjzdgRXVBn3BILgVZn+v7hYBCOeNxJ4NB5x4x6u6H7VvXOMiF +ELcZ+Oi9CJX8ljRjFn8zIiXyaPUkLHVwi+ovWbXJkYJDJJvDDwbKUuTYhLSjs7L/Ikq UifmG13rKr/xvbzJmf83fjxSub7crdEQ6GKbQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=kvDQKnIMBMiZHFmL8NwgMs4kOsCygHc5vQ7zEby9LnPjfmZZ3pWVJLwWw/WWiFPMHY xvaspg7SgaqQjXdc1AwhmUEyO57c4/HKoxMwLkBN3/S8ftjZnMBkWfwfSnnQ0U6r6gj1 MOt7zuQLzgRZ9bVxbAznbyH8kH/cs0lE22ZfY= Received: by 10.115.19.19 with SMTP id w19mr8050285wai.195.1213717354408; Tue, 17 Jun 2008 08:42:34 -0700 (PDT) Received: by 10.114.130.17 with HTTP; Tue, 17 Jun 2008 08:42:34 -0700 (PDT) Message-ID: Date: Tue, 17 Jun 2008 09:42:34 -0600 From: "Scott Marlowe" To: "Greg Smith" Subject: Re: Which hardware ? Cc: lionel@art-informatique.com, pgsql-performance@postgresql.org In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080617142501.GG68434@commandprompt.com> X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200806/77 X-Sequence-Number: 30427 On Tue, Jun 17, 2008 at 9:32 AM, Greg Smith wrote: > Considering that Lionel's system seems pretty overpowered for what he's > doing--runs plenty fast on a much slower system, enough RAM to hold a large > portion of the primary tables and database, all batch updates that don't > really need a good RAID setup--I'd say "looks good" here and recommend he > just follow the plan he outlined. Just watch the system with top for a bit > under load to make sure the Java processes are staying under control. In the original post he mentioned that he had 5 years of data at about 25G / year. With 125G of data, it's likely that if most queries are on recent data it'll be in RAM, but anything that hits older data will NOT have that luxury. Which is why I recommended RAID-10. It doesn't have to be on a $1200 card with 44 disks or something, but even 4 disks in a sw RAID-10 will be noticeably faster (about 2x) than a simple RAID-1 at hitting that old data. We had a reporting server with about 80G of data on a machine with 4G ram last place I worked, and it could take it a few extra seconds to hit the old data, but the SW RAID-10 on it made it much faster at reporting than it would have been with a single disk.