Data warehouse appliance and software appliance vendors like to claim that they've worked out just the right hardware configuration(s), and that a single configuration is correct for a fairly broad range of workloads. But there are a lot of reasons to be dubious about that. Specific vendor evidence includes:
- Teradata ascribes considerable importance to a Virtual Storage technology whose main purpose is to allow mixing of heterogeneous storage devices in a single system. And the discussion rarely suggests that these parts will be in a rigid fixed relationship.
- Netezza -- as Teradata keeps reminding me -- often sells boxes with the expectation that they won't be filled with data, so as to increase spindle count and hence performance.
- Oracle/Sun have dropped some comments about Exadata being more flexibly configured going forward.
- Kickfire's new "high-end" appliance lets you attach fairly arbitrary amounts of external storage.
- And of course, software-only analytic DBMS vendors run their software in all sorts of hardware and storage environments.