US Patent 9792298 Managing metadata and data storage for a cloud controller in a distributed filesystem

The disclosed embodiments disclose techniques for managing metadata and data storage for a cloud controller in a distributed filesystem. Two or more cloud controllers collectively manage distributed filesystem data that is stored in one or more cloud storage systems. More specifically, the cloud controllers cache and ensure data consistency for the data stored in the cloud storage systems, with each cloud controller maintaining (e.g., storing) in a local storage device: (1) one or more metadata regions containing a metadata hierarchy that reflects the current state of the distributed filesystem; and (2) cached data for the distributed filesystem. During operation, the cloud controller receives an incremental metadata snapshot that references new data written to the distributed filesystem. The cloud controller stores updated metadata from this incremental metadata snapshot in one of the metadata regions on the local storage device.