Absolutely right - I wrote an object storage backed filesystem for Hadoop and synchronizing was a complete nightmare. It certainly worked well within our requ

Absolutely right - I wrote an object storage backed filesystem for Hadoop and synchronizing was a complete nightmare. It certainly worked well within our required architecture - but as a general purpose system it would have several issues over typical network topologies. As active volume size increases and/or changes, the object storage layer latency can bump up to minutes, or even hours. We stopped tested at 100TB volumes, as the object storage layer was backed up to hours. Object Storage is very convenient, but the lack of good metadata and latencies involved basically means that it's only good as an archival backing store of active data. If your active datasource goes out - you could lose hours of data unless you have local copies.