[ddrager]

All VPS systems suffer from the "noisy neighbor" problem. You may have been on a DigitalOcean system with a lot of neighbors with other high i/o activity, and on Linode you could have been on a server with no neighbors.

The only way to test this is to get a random sampling of servers (which in of itself may be difficult) and then re-do the testing.

That is to say, on a VPS you aren't the only customer using i/o.