Roger Heflin (rogerheflin@xxxxxxxxx) 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.
