When I say volume partition, I'm referring to how to separate the different structure of your MySQL components to different volumes. For a newbie, it is so easy to just install MySQL using its default configuration. This means that your binary logs (assuming you are using it) will be in the same volume as your data files.
There is nothing wrong with this if you have a small database, but once your database grows, you will see an impact of what you did. What you sow, is what you reap. Let me explain this further, remember that binary logs needs to be written to the hard disk and the same goes for the data files. Imagine if there are two processes writing to your hard disk at the same time, what would happen? Setting aside the technological jargon, it will take longer to perform the necessary action.
This is the reason why you have to be careful in partitioning your MySQL into different volumes. Make sure that the binary logs and the data files are in a different partitions.