X-Original-To: pgsql-performance-postgresql.org@postgresql.org Received: from localhost (mx1.hub.org [200.46.208.251]) by postgresql.org (Postfix) with ESMTP id DD51F9FA5D8 for ; Wed, 14 Jun 2006 08:41:45 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.208.251]) (amavisd-new, port 10024) with ESMTP id 47352-02 for ; Wed, 14 Jun 2006 08:41:35 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey- Received: from mail.aeccom.com (port-83-236-156-26.static.qsc.de [83.236.156.26]) by postgresql.org (Postfix) with ESMTP id 755ED9F9CAA for ; Wed, 14 Jun 2006 08:41:35 -0300 (ADT) Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.aeccom.com (Postfix) with ESMTP id C940A1D018; Wed, 14 Jun 2006 13:41:33 +0200 (CEST) Received: from mail.aeccom.com ([127.0.0.1]) by localhost (gate6.aeccom.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 22199-05-3; Wed, 14 Jun 2006 13:41:32 +0200 (CEST) Received: from [192.168.2.14] (andes.core.aeccom.com [192.168.2.14]) by mail.aeccom.com (Postfix) with ESMTP id DCCBB1D016; Wed, 14 Jun 2006 13:41:32 +0200 (CEST) Message-ID: <448FF5EB.8010808@aeccom.com> Date: Wed, 14 Jun 2006 13:41:31 +0200 From: Sven Geisler Organization: AEC/communications GmbH User-Agent: Thunderbird 1.5.0.4 (Windows/20060516) MIME-Version: 1.0 To: hubert depesz lubaczewski CC: Pgsql-Performance Subject: Re: how to partition disks References: <9e4684ce0606140052m62552d41xa9364b9d4e266c97@mail.gmail.com> <448FC843.1090205@aeccom.com> <9e4684ce0606140421m1a71581dmaa7a9adb988aedc8@mail.gmail.com> In-Reply-To: <9e4684ce0606140421m1a71581dmaa7a9adb988aedc8@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: amavisd-new at aeccom.com X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200606/246 X-Sequence-Number: 19603 Hi Hupert, hubert depesz lubaczewski schrieb: > On 6/14/06, *Sven Geisler* > wrote: > You should configure your discs to RAID 10 volumes. > You should set up a separate volume for WAL. > A volume for an additional table space may also useful. > In your case I would do 2 partitions: > 1. RAID 10 with 8 discs for general data > > > raid 10 is of course not questionable. but are you sure that it will > work faster than for example: > 2 discs (raid 1) for xlog > 6 discs (raid 10) for tables > 6 discs (raid 10) for indices? > This depends on your application. Do you have a lot of disc reads? Anyhow, I would put the xlog always to a RAID 10 volume because most of the I/O for update and inserts is going to the xlog. 4 discs xlog 6 discs tables 4 discs tables2 This should be better. You should distribute indices on separate spindle stacks to share the I/O. But again this depends on your application and your server. How are the indices used? How large is your file system cache. What does PostgreSQL effectively read from disc. Don't forget to tune your postgresql.conf: Cheers Sven.