From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Robinson Subject: Re: 3TB drives failure rate (summary) Date: Thu, 01 Nov 2012 16:05:50 +0000 Message-ID: <50929DDE.60906@anonymous.org.uk> References: <11510711257.20121028131527@oudeis.org> <508D61A1.7020106@wildgooses.com> <508D65CF.1080904@gmail.com> <508DADC3.4080104@shiftmail.org> <508DB08D.20002@meetinghouse.net> <508DC6E9.8070001@shiftmail.org> <508DC922.7040400@meetinghouse.net> <20121029102919.1134a797@natsu> <508E3626.8080404@hesbynett.no> <508E7E68.1030202@turmel.org> <1494377384.20121031005457@oudeis.org> <50911AFF.9020707@turmel.org> <509291B2.5000907@meetinghouse.net> <50929430.50201@anonymous.org.uk> <509297CA.4090606@meetinghouse.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <509297CA.4090606@meetinghouse.net> Sender: linux-raid-owner@vger.kernel.org To: Miles Fidelman Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On 01/11/2012 15:39, Miles Fidelman wrote: > John Robinson wrote: >> On 01/11/2012 15:13, Miles Fidelman wrote: >>> Phil Turmel wrote: >>>> I strongly encourage you to run "smartctl -l scterc /dev/sdX" for each >>>> of your drives. For any drive that warns that it doesn't support SCT >>>> ERC, set the controller device timeout to 180 like so: >>>> >>>> echo 180 >/sys/block/sdX/device/timeout >>>> >>>> If the report says read or write ERC is disabled, run "smartctl -l >>>> scterc,70,70 /dev/sdX" to set it to 7.0 seconds. >>>> >>>> You then set up a boot-time script to do these adjustments at every >>>> restart. >>> >>> Sounds like a very bad idea if your drive is part of a RAID array. >> >> Either of these - the scterc if you can, the device timeout if you >> can't - are an excellent idea if you are using a desktop drive as part >> of a md RAID array. Why do you think otherwise? > > If I'm seeing that kind of device timeout, I want it out of my array, > and I want an alert telling me to replace it. Otherwise my server's > performance goes to s*&t. You might not want that kind of device timeout, but as you've made clear earlier in this thread, you wouldn't use desktop drives in md RAID, so this doesn't really apply to you. Anyone using desktop drives which don't support SCT ERC in md RAID is liable to see long timeouts on the simplest bad sector, and they probably prefer to keep the drive in the array and have the sector rewritten after reconstruction than have the drive failed out of the array. Cheers, John.