From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfgang Denk Subject: Re: Huge values of mismatch_cnt on RAID 6 arrays under Fedora 18 Date: Tue, 29 Jan 2013 00:18:39 +0100 Message-ID: <20130128231840.03C37203AD5@gemini.denx.de> References: <20130127192656.634892005AD@gemini.denx.de> <20130128173704.GA2329@lazy.lzy> <20130128190035.D943A294BAB@gemini.denx.de> <20130128191041.8E962200607@gemini.denx.de> <20130128192256.GB13803@lazy.lzy> <20130128201947.2B615200607@gemini.denx.de> <20130128204422.GA14115@lazy.lzy> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: In-reply-to: <20130128204422.GA14115@lazy.lzy> Sender: linux-raid-owner@vger.kernel.org To: Piergiorgio Sartor Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids Dear Piergiorgio Sartor, In message <20130128204422.GA14115@lazy.lzy> you wrote: > > It could still be the data is as it was written, > but, for some reasons I could not imagine, the > parities (both) are not correct. This is what I think at the moment, as all my samples of data so fare looked ok. > This could be in case of some software bug, which > would be quite a surprise, I must say. Indeed. Guess how I feel... > Still, would be nice to check if the whole array > is it this state or if, sooner or later, some > knwon slot (with error) is found somewhere else. Checks still running. I see two things: - on the array where I was running "repair" before, raid6check reports no errors so far - but still there is a mismatch_cnt = 362731480 raid6check is still running. - on the second machine, I have 558579 lines out output, 176 of which are errors of type "Error detected at : disk slot unknown"; no other errors reported so far. raid6check is still running. - on the third machine, I have 5512894 lines out output, 1599431 of which are errors of type "Error detected at : disk slot unknown"; no other errors reported so far. raid6check is still running. This smells really bad as if parity computation was broken... OK, add more hardware details... A: Supermicro X8SAX mainboard, Core i7 CPU 950 @ 3.07GHz, 24 GB RAM H: Supermicro X8ST3 mainboard, Xeon CPU W3565 @ 3.20GHz, 24 GB RAM X: Supermicro X8SAX mainboard, Core i7 CPU 950 @ 3.07GHz, 24 GB RAM Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de What is research but a blind date with knowledge? -- Will Harvey