Am 30.03.20 um 14:18 schrieb Paul Menzel:

How do you run `mdcheck` in production without noticeably affecting the
system?

you can' for years

either lower "dev.raid.speed_limit_max" and wait ages for the raid check
or cripple system performance

i remember "dev.raid.speed_limit_max" did 10 years ago what it is
supposed to do: use that when the system is idle but slow down the
raid-check in case of heavy user-io

but the current drama exists for many years