X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 23B19D78B7 for ; Wed, 24 Aug 2005 13:35:08 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 92951-07 for ; Wed, 24 Aug 2005 16:35:03 +0000 (GMT) Received: from wproxy.gmail.com (wproxy.gmail.com [64.233.184.200]) by svr1.postgresql.org (Postfix) with ESMTP id 37124D7897 for ; Wed, 24 Aug 2005 13:35:02 -0300 (ADT) Received: by wproxy.gmail.com with SMTP id i22so132067wra for ; Wed, 24 Aug 2005 09:35:01 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=b0N2msU1qLDiAm9q/iyXDo63t1Y8GDD9kVYQX8Fl2+PfWQHNHaiIpnVAY8fe0f34IBLM6/MBL3TLn3xHMh6cjnh2pIbdpxCrkPoiBb/G9CI6PV55k/6MgBmMLig9+2xwWBfncoEoNwTBUJBAQYstyQ5PCiJhp0FakRYSkY06ww4= Received: by 10.54.111.11 with SMTP id j11mr839076wrc; Wed, 24 Aug 2005 09:35:01 -0700 (PDT) Received: by 10.54.96.7 with HTTP; Wed, 24 Aug 2005 09:35:01 -0700 (PDT) Message-ID: <37d451f70508240935315add63@mail.gmail.com> Date: Wed, 24 Aug 2005 11:35:01 -0500 From: Rosser Schwarz To: Alexandre Barros Subject: Re: performance drop on RAID5 Cc: postgres performance In-Reply-To: <430C8779.9080500@vectorx.com.br> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline References: <430C8779.9080500@vectorx.com.br> X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.089 required=5 tests=[AWL=0.065, RCVD_BY_IP=0.024] X-Spam-Level: X-Archive-Number: 200508/389 X-Sequence-Number: 14136 On 8/24/05, Alexandre Barros wrote: > i wouldn't be so stunned if the newer machine was ( say ) twice faster > than the older server, but over three times faster is disturbing. RAID5 on so few spindles is a known losing case for PostgreSQL. You'd be far, far better off doing a pair of RAID1 sets or a single RAID10 set. /rls --=20 :wq