From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Patrick H." Subject: Re: filesystem corruption Date: Wed, 05 Jan 2011 08:55:17 -0700 Message-ID: <4D249465.3060103@feystorm.net> References: <4D212D4A.3040003@feystorm.net> <20110103141603.632fdf3e@notabene.brown> <4D247FFB.3090209@feystorm.net> <4D2493A4.9010209@shiftmail.org> Mime-Version: 1.0 Content-Type: text/plain; charset=KOI8-R; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4D2493A4.9010209@shiftmail.org> Sender: linux-raid-owner@vger.kernel.org To: linux-raid List-Id: linux-raid.ids HP DL360-G6. SAS controller with battery backed write accelerator. I havent been focusing on the reliability of the drives as this is proof of concept testing. If we decide to use it, the drives will be replaced with 2TB SSD PCIe cards. -Patrick Sent: Wed Jan 05 2011 08:52:04 GMT-0700 (Mountain Standard Time) From: Spelic To: Patrick H. linux-raid Subject: Re: filesystem corruption > On 01/05/2011 03:28 PM, Patrick H. wrote: >> No, my drives are battery backed as well. > > what drives are they, if I can ask? OCZ SSDs with supercapacitor maybe? > > Do you know if they will really flush the whole write cache on sudden > power off? I read smoky sentences about this for the OCZ drives. In > certain points it seemed like the supercapacitor was only able to > provide the same guarantees of a HDD, that is, no further data loss > due to erase-then-rewrite-32K and flash wear levelling stuff, but was > not able to flush the write cache. > Did you try with e.g. a stream of simple databases transactions then > disconnecting the cable suddenly like this test > http://www.mysqlperformanceblog.com/2009/03/02/ssd-xfs-lvm-fsync-write-cache-barrier-and-lost-transactions/ > > ? > > Thank you