Other Research on Scalable Storage Clusters (none in production yet) Ceph – Sage Weil, UCSC : POSIX lite ◦ Multiple metadata servers, dynamic workload balancing ◦ Mathematical hash to map file segments to nodes Sorrento – UCSB : POSIX with low write-sharing ◦ Distributed algorithm for capacity and load balancing, distributed metadata ◦ Lazy consistency semantics Ward Swarms – Lee Ward, Sandia ◦ Similar to Sorrento, uses victim cache and storage tiering