There are some compromises that you'll need to make; there are certainly some control granularity issues. The pattern...
of access for file-based data and block-based data is significantly different.
As a result, a lot of these [unified or multiprotocol storage] systems don't have the granularity of control needed to understand how to handle file-based I/O versus block-based I/O. This leads to compromises in performance and could lead to variability in performance. As you move into more performance-critical environments, consistency of performance becomes more important. If a block-based application is combined on a system that has more dynamic file-based access, users can experience variability in performance because of resources allocated to the file-based side.
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