Implementing high performance in enterprise storage is a constant battle to find and eliminate the next system bottleneck. Normally this alternates between limits of the underlying media and the computational overhead of metadata management, but choosing the wrong approach to deduplication can introduce a third performance challenge that can be impossible to overcome. Storage that implements a multi-pass approach to data optimization, such as staged or post-process deduplication, becomes inherently at a disadvantage for both computational and media overhead.
Source: Open Source