OVH NVME atop Reporting Problem

Upon installation empty idle server with NVME disks reports unusual high NVME disk usage using atop command:

It seems to be caused by the error in the kernel: https://github.com/Atoptool/atop/issues/47

As OVH kernel upgrade procedure is messed up, and new kernels (as of 2020-08-13) does not have a fix, a faster workaround is to set the NVMe device's I/O scheduler to 'mq-deadline' instead of the default 'none'

On Centos 7 this can be done like this:

chmod +x /etc/rc.d/rc.local

echo "# fixing messed up nvme disk usage reporting in the atop for OVH server" >> /etc/rc.d/rc.local
echo "echo mq-deadline > /sys/block/nvme0n1/queue/scheduler" >> /etc/rc.d/rc.local
echo "echo mq-deadline > /sys/block/nvme1n1/queue/scheduler" >> /etc/rc.d/rc.local

reboot

Make sure that you actually have nvme0n1 and nvme1n1 devices on your system. Check with atop and change accordingly.

After that the problem is gone:

See also

• OVH server installation
• OVH server Rescue Mode