Messages in this thread | | | From | "Justin Piszcz" <> | Subject | 3.12: raid-1 mismatch_cnt question | Date | Mon, 4 Nov 2013 05:25:28 -0500 |
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Hi,
I run two SSDs in a RAID-1 configuration and I have a swap partition on a third SSD. Over time, the mismatch_cnt between the two devices grows higher and higher.
Once a week, I run a check and repair against the md devices to help bring the mismatch_cnt down. When I run the check and repair, the system is live so there are various logs/processes writing to disk. The system also has ECC memory and there are no errors reported.
The following graph is the mismatch_cnt from June 2013 to current; each drop represents a check+repair. In September, I dropped the kernel/vm caches before running check/repair and that seemed to help a bit. http://home.comcast.net/~jpiszcz/20131104/md_raid_mismatch_cnt.png
My question is: is this normal or should the mismatch_cnt always be 0 unless there is a HW or md/driver issue?
Justin.
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