Whenever I encounter an IO issue, I always frame it in terms of Oracle and application requirements, and IO subsystem capacity. This not only implies there are three areas to focus on for solutions, but it immediately disarms everyone involved (that is, unless they really messed up and performed what I call a career decision).

I have seen the IO subsystem misconfigured. Vendors won't admit this as a possibility until cornered with both Oracle and operating system tracing proof. Usually, the problem is a physical connection issue, where too much IO activity is going through too few connections. A relatively simple reconfiguration can actually solve the problem.

In most cases, however, everyone must get involved to solve the problem. This means DBAs focused on Oracle and balancing the workload; DBAs, vendors, and developers working on the SQL; and IO administrators somehow increasing IO capacity. Eventually, nearly every Oracle system outgrows its IO subsystem, and additional capacity must be added. But proving this is not our initial objective. We are problem-solvers, not salespeople!