I have been working on a site for the past few of hours and everything has been running smoothly. About an hour ago every single page load suddenly started taking so long that most of them time out. I haven't changed anything with the queries or the database so I can't figure what is causing this. These queries are ridiculously simple and used to require upwards of 5 seconds to load the whole page at most.
When I look at MySQL in the Windows task manager I see that it isn't using much CPU power, nor is anything else. However, my hard drive light is going non-stop when I try to load a page and whenever the page times out it is always on a line of code fetching a query result from the database.
What could MySQL have suddenly started doing that even simple queries require vast amounts of hard drive usage?