View source for OVH NVME atop Reporting Problem

Upon installation empty idle server with NVME disks reports unusual high NVME disk usage using [https://www.tecmint.com/how-to-install-atop-to-monitor-logging-activity-of-linux-system-processes/ atop] command:

[[File:ovh_nvme_high.png]]

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

As [https://docs.ovh.com/gb/en/dedicated/updating-kernel-dedicated-server/ 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:

[[File:ovh_nvme_low.png]]

[[File:ovh_nvme_low_graph.png]]

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== See also ==
* [[OVH server installation]]
* [[OVH server Rescue Mode]]