Received: from localhost (unknown [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id 837FE9FB433 for ; Fri, 7 Sep 2007 10:16:25 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-maia, port 10024) with ESMTP id 16406-10 for ; Fri, 7 Sep 2007 10:16:14 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from vms044pub.verizon.net (vms044pub.verizon.net [206.46.252.44]) by postgresql.org (Postfix) with ESMTP id AC3C49FB54E for ; Fri, 7 Sep 2007 10:16:20 -0300 (ADT) Received: from osgiliath.mathom.us ([96.231.24.225]) by vms044.mailsrvcs.net (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) with ESMTPA id <0JO0009PE26URPL4@vms044.mailsrvcs.net> for pgsql-performance@postgresql.org; Fri, 07 Sep 2007 08:16:06 -0500 (CDT) Received: from localhost (localhost [127.0.0.1]) by osgiliath.mathom.us (Postfix) with ESMTP id 081DF1F816; Fri, 07 Sep 2007 09:16:05 -0400 (EDT) Received: from osgiliath.mathom.us ([127.0.0.1]) by localhost (osgiliath.home.mathom.us [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 2LJ8VDjMlN77; Fri, 07 Sep 2007 09:16:04 -0400 (EDT) Received: by osgiliath.mathom.us (Postfix, from userid 1000) id E11121F80D; Fri, 07 Sep 2007 09:16:03 -0400 (EDT) Date: Fri, 07 Sep 2007 09:16:03 -0400 From: Michael Stone Subject: Re: SAN vs Internal Disks In-reply-to: <20070907103341.GC20896@oppetid.no> To: Tobias Brox Cc: pgsql-performance@postgresql.org Mail-followup-to: Tobias Brox , pgsql-performance@postgresql.org Message-id: <20070907131601.GG1795@mathom.us> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii; format=flowed Content-disposition: inline X-Virus-Scanned: Debian amavisd-new at mathom.us X-Pgp-Fingerprint: 53 FF 38 00 E7 DD 0A 9C 84 52 84 C5 EE DF 7C 88 References: <20070907100446.GE1795@mathom.us> <20070907103341.GC20896@oppetid.no> User-Agent: Mutt/1.5.13 (2006-08-11) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200709/126 X-Sequence-Number: 26671 On Fri, Sep 07, 2007 at 12:33:41PM +0200, Tobias Brox wrote: >Advantages: > > 1. Higher I/O (at least the salesman claims so) Benchmark it. It is extremely unlikely that you'll get I/O *as good as* DAS at a similar price point. > 2. Easier to upgrade the disk capacity Is this an issue? You may find that you can simply get dramatically more space for the money with DAS and not have to worry about an upgrade. Also, you can use the postgres tablespace functionality to migrate data to a new partition fairly transparently. > 3. Easy to set up "warm standby" functionality. (Then again, if the > postgres server fails miserably, it's likely to be due to a disk > crash). You may find that using db replication will gain you even more reliability for less money. >Also, my boss states that "all big enterprises uses SAN nowadays". Use SAN *for what*? Mike Stone