From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stan Hoeppner Subject: Re: /dev/md2 stopped after changing SAS controller Date: Sat, 14 May 2011 13:19:44 -0500 Message-ID: <4DCEC7C0.80306@hardwarefreak.com> References: <20110513202900.GA1926@apartia.fr> <4DCE99D0.1010900@hardwarefreak.com> <20110514151812.GA3074@apartia.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20110514151812.GA3074@apartia.fr> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids On 5/14/2011 10:18 AM, Louis-David Mitterrand wrote: > On Sat, May 14, 2011 at 10:03:44AM -0500, Stan Hoeppner wrote: >> On 5/13/2011 3:29 PM, Louis-David Mitterrand wrote: >> >>> I've been having very bad performance with an LSISAS2008 controller >>> attached to 8 WD Caviar Black 1TB disks. >> >> What is the nature of this 'very bad performance'? Did you recently >> upgrade kernel/driver and run into a regression? If not, either the HBA >> has developed a circuit defect, or the problem lies elsewhere, either a >> backplane/cabling issue, or a drive going south. > > The performance problem can be clearly attributed to that model of the > LSI card because with the Adaptec card and the same cables and disks the > problem disappears. How have you ascertained this already? As of 2 hours ago you still don't have your filesystem(s) back up and running after the HBA swap. I would assume a backup restore of a few TB would take more than a few hours... > The LSI card has always performed very poorly with all kernel versions I > tried, including the very latest, and the with most recent firmware > revisions from LSI. LSI HBAs are usually held in pretty high regard. Which specific part# are we talking about? Is this an OEM Dell HBA? > After bricking the card while trying to change its firmware to an "IT" > version (Initiatior Target i.e. non-raid) I had Dell send me a new one > on warranty and the performance problem remained. You still haven't described the nature of the performance problem. This is a technical mailing list after all. >> Do you have any log entries showing problems with the LSI HBA? Drive >> errors? What does smartctl tell you about each drive? > > No error. Just plain sloth. Interesting technical description. Now we have yet another post in the Interwebs archives stating a certain piece of hardware is junk without any real explanation as to the nature of the problem... -- Stan