X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 56E659DD64B for ; Thu, 1 Dec 2005 08:44:34 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 64168-04 for ; Thu, 1 Dec 2005 08:44:25 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from bfccomputing.com (bfccomputing.com [217.160.248.65]) by postgresql.org (Postfix) with ESMTP id 53B359DD5F5 for ; Thu, 1 Dec 2005 08:44:27 -0400 (AST) Received: from [10.0.0.42] (68-169-200-61.sbtnvt.adelphia.net [68.169.200.61]) by bfccomputing.com (Postfix) with ESMTP id 6E902E8117; Thu, 1 Dec 2005 07:44:23 -0500 (EST) In-Reply-To: <00d101c5f63b$33348330$3cd7adc0@julia> References: <00d101c5f63b$33348330$3cd7adc0@julia> Mime-Version: 1.0 (Apple Message framework v623) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: Content-Transfer-Encoding: 7bit Cc: From: Bill McGonigle Subject: Re: About the relation between fragmentation of file and VACUUM Date: Thu, 1 Dec 2005 07:44:22 -0500 To: "Tatsumi Abe" X-Mailer: Apple Mail (2.623) X-bfccomputing-MailScanner-Information: Please contact the ISP for more information X-bfccomputing-MailScanner: Found to be clean X-bfccomputing-MailScanner-SpamCheck: X-MailScanner-From: bill@bfccomputing.com X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0 required=5 tests=[none] X-Spam-Score: 0 X-Spam-Level: X-Archive-Number: 200512/6 X-Sequence-Number: 15827 On Dec 1, 2005, at 00:50, Tatsumi Abe wrote: > However, In my current environment I can't stop PostgreSQL and cancel > fragmentation. > > Could anyone advise some solutions for this fragmentation problem > without stopping PostgreSQL ? This is somewhat of an aside and intended just as a helpful suggestion since I've been in this spot before: if you have this kind of uptime requirement the first project to work on is getting the environment to the point where you can take out at least one database server at a time for maintenance. You're going to be forced to do this sooner or later - whether by disk failure, software error (Pg or OS), user error (restore from backup) or security issues (must patch fixes). So disk fragmentation is a great thing to worry about at some point, but IMHO you've got your neck under the guillotine and worrying about your cuticles. I've heard the arguments before, usually around budget, and if the company can't spend any money but needs blood-from-stone performance tweaks, somebody isn't doing the math right (I'm assuming this isn't running on a satellite). Plus, your blood pressure will go down when things are more resilient. I've tried the superhero thing before and it's just not worth it. -Bill ----- Bill McGonigle, Owner Work: 603.448.4440 BFC Computing, LLC Home: 603.448.1668 bill@bfccomputing.com Mobile: 603.252.2606 http://www.bfccomputing.com/ Pager: 603.442.1833 Jabber: flowerpt@gmail.com Text: bill+text@bfccomputing.com Blog: http://blog.bfccomputing.com/