Not everybody takes that approach. We developed HopsFS by re-implementing the metadata layer for HDFS as a distributed scale-out layer (paper being presented in

Not everybody takes that approach. We developed HopsFS by re-implementing the metadata layer for HDFS as a distributed scale-out layer (paper being presented in Usenix FAST next month - https://www.usenix.org/conference/fast17/technical-sessions https://www.usenix.org/conference/fast17/technical-sessions). As a researcher, this was not a good idea, as it has taken us many years. Time-to-market for our paper was extremely slow, but the upshot is that we have a production system. The big risk for us was that our work would not be seen as relevant when we were finished, and it has been a high risk research angle to take.