Hitachi Vantara Corporation

Robert Cooper

Alan Bryant

Nathan W Clark

Walter Wohler

Clayton Alan Curry

Marty Kulma

Charles C Bennett, Jr

Morgan Tyler Maxwell

Kevin S Canuette Grimaldi

In some examples, a plurality of nodes may each host a respective logical database (LDB) that includes database data that references external resources stored in a storage system. Further, each node may maintain, for each external resource referenced by the respective LDB on that node, a reference count of a number of references in the respective LDB to each external resource and a timestamp associated with the reference count. In response to addition of a reference to a particular external resource in a particular LDB, a node that hosts the particular LDB may be programmed to increment the reference count and update the timestamp for the particular external resource. Similarly, in response to removal of the reference to the particular external resource in the particular LDB, the node hosting the particular LDB is programmed to decrement the reference count and update the timestamp for the particular external resource.

Deduplication and garbage collection across logical databases

In some examples, both object data and corresponding metadata are stored on thin provisioned block storage in which blocks for the storage of the object data and the metadata are dynamically provisioned from a shared pool. For instance, the metadata may be stored on the block storage using a tree data structure that may grow proportionally with the corresponding stored object data. The object storage may automatically adapt to the size and number of objects being stored, and storage space for metadata may be allocated dynamically on demand. Additionally, some implementations include storing data across multiple trays. For instance, a plurality of storage extents of an extent group may be allocated across a plurality of storage devices on multiple trays. The extent allocation may be tray-aware by allocating extents to maximize the probability that data remains available/recoverable in the presence of a failure in one or more trays.

Elastic metadata and multiple tray allocation

Growing community of inventors

Somerville, MA, United States of America

Robert Cooper