I have a VPS with a hosting provider. Recently, I discover that my load average is just extremely high. I have a 2 core VPS, and the load average can go up to 9 or 10, as shown below!
I initially thought that this was because my CPU/RAM not enough, however, the VPS provider told me that it could be that my IO load is very heavy ( or other VPS on the same dedicated machine's IO load) is heavy.
I have no way to verify the claim.
Anyway I can check the usage of IO? And can I know whether the high IO usage is due to my VPS, or other VPS cohabitat on the same physical machine?
Looking at the screen-shot you posted I can see that your VPS is on OpenVZ container based virtualization. Unfortunately,there is no way for you check IO stats due to how container based virtualization works. Your host is correct that the IO load will reflect in your load average,however this seems strange. Normally disk IO isn't what pushes you to a high load average,but CPU access or load causes the problem.
I would postulate that your host is giving you a bogus answer to cover up massive over-utilization/overselling or abuse of the node by another client. Your host should be able to give you a better idea on if the high load is caused by Disk IO or CPU , and if they can't I'd suggest finding a new provider. ( I work for a web host and manage OpenVZ nodes as my day job.)