Is it being rebuilt, causing higher IO?: http://serendipity.ruwenzori.net/index.php/2007/08/06/mdadm-rebuild20-event-de tected-on-md-device Or could you have replaced a drive at some point and had an alignment mis-match? If they seem "healthy" to mdadm, I would go with the suggestions to check the smart counters on the drives as others have suggested. This document might be a bit old, but might give you some places to look as well: http://tldp.org/HOWTO/Software-RAID-HOWTO-6.html Kelly > Thu Jul 14 2016 03:37:58 PM CDT from "gregrwm" <tclug1 at whitleymott.net> >Subject: Re: [tclug-list] raid corrupted? but no clue from mdstat > > the first report had numbers for all devices, the second and third for >sda&sdb only, and the 4th and onward are all zeros. which is probably just >right for a quiescent box. but mdadm still has the CPU pinned. > > > On Thu, Jul 14, 2016 at 12:46 PM, kelly <kelly.black at penguinpackets.com> >wrote: > >> >> >>Does iostat give any clues as to which drive is busy (i.e. more busy than >>the others as far as % usage?) >> >>iostat -d -x 1 >> >>Is the LVM ok otherwise? >> >>Kelly >>> Thu Jul 14 2016 12:32:24 PM CDT from "gregrwm" <tclug1 at whitleymott.net> >>>Subject: [tclug-list] raid corrupted? but no clue from mdstat >>> >>> what's up with my mdadm? note how it's taking 97% of CPU: >>>.... >>> >>> >>> >>> >>> >>> >>> >>> >> >> >> > > > > > > > > > > > (, 0 bytes) [View| Download] > > > > > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mailman.mn-linux.org/pipermail/tclug-list/attachments/20160714/106a26c8/attachment.html> -------------- next part -------------- An embedded and charset-unspecified text was scrubbed... Name: URL: <http://mailman.mn-linux.org/pipermail/tclug-list/attachments/20160714/106a26c8/attachment.ksh>