From mboxrd@z Thu Jan 1 00:00:00 1970 From: Justin Piszcz Subject: Re: mismatch_cnt != 0 Date: Sat, 23 Feb 2008 09:05:10 -0500 (EST) Message-ID: References: <47C01D79.4010708@msgid.tls.msk.ru> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Return-path: In-Reply-To: <47C01D79.4010708@msgid.tls.msk.ru> Sender: linux-raid-owner@vger.kernel.org To: Michael Tokarev Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On Sat, 23 Feb 2008, Michael Tokarev wrote: > Justin Piszcz wrote: >> Should I be worried? >> >> Fri Feb 22 20:00:05 EST 2008: Executing RAID health check for /dev/md3... >> Fri Feb 22 21:00:06 EST 2008: cat /sys/block/md3/md/mismatch_cnt >> Fri Feb 22 21:00:06 EST 2008: 936 >> Fri Feb 22 21:00:09 EST 2008: Executing repair on /dev/md3 >> Fri Feb 22 22:00:10 EST 2008: cat /sys/block/md3/md/mismatch_cnt >> Fri Feb 22 22:00:10 EST 2008: 936 > > Your /dev/md3 is a swap, right? > If it's swap, it's quite common to see mismatches here. I don't know > why, and I don't think it's correct (there should be a bug somewhere). > If it's not swap, there should be no mismatches, UNLESS you initially > built your array with --assume-clean. > In any case it's good to understand where those mismatches comes from > in the first place. > > As of the difference (or, rather, lack thereof) of the mismatched > blocks after check and repair - that's exactly what expected. Check > found 936 mismatches, and repair corrected exactly the same amount > of them. I.e., if you run check again after repair, you should see > 0 mismatches. > > /mjt > My /dev/md3 is my main RAID 5 partition. Even after repair, it showed 936, I will re-run repair. Also, I did not build my array with --assume-clean and I run my check > array once a week. Justin.