Re: Cannot change RAID array check speed

[simd@vfemail.net]

It worked with LK 6.9 on Devuan (Debian Stretch) ASCII.

I upgraded the system, both HW and SW, to Daedalus and I had to go with a
newer kernel to use the newer Intel iGPU. I'm now on Devuan (Debian
Bookworm) Daedalus.

I used to change this value all the time to get the check done faster or
to slow it down because I needed to access the array.

Maybe it's a distro security policy? IDK. But as I said, I used to change
it all the time. That's why there's a sync_speed_min/max, or so I thought.

Thanks,
David

PS: Accidentally sent to the user instead of to the list. Sorry.


On Mon, 16 Feb 2026 06:20:58 +0100
Dragan Milivojević <galileo@pkm-inc.com> wrote:
> When did that work?
> /sys/devices/virtual/ etc
> is readonly on 4.18,  6.12 and  6.18 (a few boxes that I have).
> 
> 
> 
> On Mon, 16 Feb 2026 at 04:15, David Niklas <simd@vfemail.net> wrote:
> >
> > Hello,
> > I upgraded my kernel from 6.9 to 6.17. They're both the "same" custom
> > config. I tried:
> >
> > # echo 200000 > /sys/devices/virtual/block/md7/md/sync_speed
> > bash: /sys/devices/virtual/block/md7/md/sync_speed: Permission denied
> > # id
> > uid=0(root) gid=0(root) groups=0(root)
> >
> > This used to work. Any ideas as to what I could have set wrong? I
> > haven't a clue!
> >
> > Is there a security debugging tool or a log-file I could use to trace
> > this down?
> >
> > Thanks,
> > David
> >