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Subject: Re: problem with recovered array
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Roger Heflin (rogerheflin@gmail.com) wrote on Tue, Oct 31, 2023 at 11:19:24AM -03:
> You might also want to look at the io for the sd* devices under the md
> device as that would show what MD is doing under the covers to make
> the io happen (sar and/or iostat).

Exactly. Guess what disks are doing? Nothing! That's the whole point. The
kernel becomes unable to send writes to the disks and the flushd thread remains
using 100% cpu.

Again: this is not an excess of writes that the array cannot cope with. On the
contrary, it's an absence of writes.