You might encounter the following problem when working on a a OpenVZ virtual host:
diskio.c: cannot find statistics in /proc/partitions
The reason why you are experiencing that is because OpenVZ Virtuozzo as well as some other VPS solutions don’t offer access to /proc/partitions. The whole /proc partition is a virtual filesystem (procfs). The structure is maintained in the kernel.
To find out more about this problem go here:
https://askubuntu.com/questions/256636/proc-partitions-not-found-error-is-showing-up