Pagiolatch_sh is counted when you do physical I/O's from your queries. It depends on what you expect from your queries whether this wait is a problem. If you expect a lot of physical I/O: it's not a problem.
What is important in this case is wait time: if the average wait time is higher then, say, 10ms, you do have an I/O performance problem. (I use 10ms as an example, but this is maybe a little high if you run against ahigh-end hardware raid disk config)