Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id A6911B5DBDC for ; Wed, 24 Aug 2011 15:48:16 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 07156-03 for ; Wed, 24 Aug 2011 18:48:10 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from webmail-out.lnh.mail.rcn.net (webmail-out.lnh.mail.rcn.net [207.172.157.109]) by mail.postgresql.org (Postfix) with ESMTP id CE354B5DBC4 for ; Wed, 24 Aug 2011 15:48:09 -0300 (ADT) Received: from ms14.lnh.mail.rcn.net ([208.58.56.82]) by smtp02.lnh.mail.rcn.net with ESMTP; 24 Aug 2011 14:48:09 -0400 Received: (from ms14.lnh.mail.rcn.net [69.183.40.171]) by ms14.lnh.mail.rcn.net (MOS 4.2.3-GA) with HTTP/1.1 id BWQ93988 (AUTH gnuoytr@rcn.com); Wed, 24 Aug 2011 14:48:09 -0400 (EDT) From: Subject: Re: Reports from SSD purgatory To: pgsql-performance@postgresql.org X-Mailer: Mirapoint Webmail Direct 4.2.3-GA MIME-Version: 1.0 In-Reply-To: <4E49B0A0.2060705@2ndQuadrant.com> References: <4E49B0A0.2060705@2ndQuadrant.com> Message-Id: <201108241848.061232@ms14.lnh.mail.rcn.net> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Date: Wed, 24 Aug 2011 14:48:09 -0400 (EDT) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.9 tagged_above=-10 required=5 tests=BAYES_00=-1.9 X-Spam-Level: X-Archive-Number: 201108/279 X-Sequence-Number: 44726 ---- Original message ---- >Date: Mon, 15 Aug 2011 19:49:52 -0400 >From: pgsql-performance-owner@postgresql.org (on behalf of Greg Smith ) >Subject: [PERFORM] Reports from SSD purgatory >To: "pgsql-performance@postgresql.org" > >News update for anyone else who's trapped like me, waiting for a fix to >the Intel 320 SSD bug where they can truncate themselves to 8MB. Over >the weekend Intel has announced a firmware fix for the problem is done, >and is due to ship "within the next two weeks": >http://communities.intel.com/thread/24121 > >On the larger SSD reliability front, Tom's Hardware surveyed heavy SSD >users they're friendly with who use Intel drives. The most interesting >data came from Softlayer: >http://www.tomshardware.com/reviews/ssd-reliability-failure-rate,2923-6.html > >This supports two claims I made before based on my private data that >were controversial: > >-Annualized SSD failure rates are not significantly lower than >traditional drives in the first couple of years. Jury is still out on >whether they will spike upwards starting at 3 years as mechanical ones do. > >-The most common source of dead drives is sudden, catastrophic >electronics failure. These are not predicted by SMART, and have nothing >to do with hitting the drive's wear limits. It's worth knowing exactly what that means. Turns out that NAND quality is price specific. There's gooduns and baduns. Is this a failure in the controller(s) or the NAND? Also, given that PG is *nix centric and support for TRIM is win centric, having that makes a big difference in performance. > >-- >Greg Smith 2ndQuadrant US greg@2ndQuadrant.com Baltimore, MD >PostgreSQL Training, Services, and 24x7 Support www.2ndQuadrant.us > > >-- >Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) >To make changes to your subscription: >http://www.postgresql.org/mailpref/pgsql-performance